# Sticky  Testing Chinese Tubes



## Henry the Hermit

I've owned a Dankung Jungle Hunter II for more than a year. Right up front, I'll say I don't like the Dankung, but I do like the thin Chinese tubes. I plan to test a variety of configurations, and will use the Dankung because of the ease of changing tubes. To kick things off, here are the results I got from the original OEM bandset, which I assume were 1745.

Pull weight at 30 inches - 19 pounds
Velocity -
.375 lead ball (75 grains) - 192 fps avg 5 shots
.429 lead ball (115) grains - 182 fps avg 5 shots
.495 lead ball (175 grains) - 161 fps avg 5 shots
Note: all measurements were made with my computer and Audacity. Later I will compare the computer measurements against my Chrony.
* Velocity measured at my normal 34 inches draw.

Further testing will be with 1842 because that is what I have.

Now I'm going outside to make some Chrony measurements.


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## Henry the Hermit

I just spent an enjoyable hour shooting and recording Chrony readings.

The first step was to measure a Cholita with #107s to see how close the Chrony is to my previous computer measurements. I got a 5 shot average with .375 lead of 185.4 fps vs 178.7 with the computer, a difference that could easily be caused by warmer weather or a slighter longer draw. Close enough.

Then I compared my older Lee mold ammo against the newer (and slighter smaller Do-It mold ammo. The Lee balls measure .375 and weigh 75 grains, the Do-It balls are .364 and weigh 71 grains. Using 1842 tubes cut to OEM length with a Jim Harris pouch on the Dankung frame, the Lees averaged 212 fps and the Do-Its averaged 212.4 fps.

Next I shot a round with Do-It .31 cal. (actual diameter .304, weight 40 grains) for a 5 round average of 235 fps.

Having already measured the 3/8 inch balls, next up was .429 lead, calculated weight 115 grains. They zipped in at 202 fps.

Finally to round out the doubled 1842 tests I shot .495 balls, calculated weight 175 grains for a 5 round average of 184.4 fps.

Next up, some surprising results with "tapered" single 1842 tubes.


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## Charles

Nice results!!! Keep 'em coming.

Cheers ..... Charles


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## Henry the Hermit

Just a teaser. I took a few shots this morning (OK, about 50), and with lightweight ammo, I am confident of hitting 300+ fps with Chinese 1842 tubes. I'm averaging 285 fps and one shot went 293 with .25 cal (6.35mm) steel. I'm hitting 260+ with .30 lead.


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## Charles

Impressive results with that lead. Will be interested to see what setup you are using.

Have a great Christmas.

Cheers ........ Charles


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## timdix

I'm pleased to see those readings with 1842. I'm waiting for some Dankung 1842 to arrive for a round of testing myself.
Can I suggest you try a mixed set up: double 1842 fork side and single at the pouch side using the longest draw possible. I'd be very interested to see your results.
My tests with 1745 with a mixed set up rival taper flats! The draw however is almost a tad heavy for 3/8 steel.
I suspect 1842 with 3/8 using this setup would be ideal:easy draw,300fps speeds,shot count well into the hundreds. The real kicker is that the tubes are so easy to cut and change not to mention cheap(if you're just changing the single strand component).


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## Rayshot

Henry in Panama said:


> I've owned a Dankung Jungle Hunter II for more than a year. Right up front, I'll say I don't like the Dankung, but I do like the thin Chinese tubes. I plan to test a variety of configurations, and will use the Dankung because of the ease of changing tubes. To kick things off, here are the results I got from the original OEM bandset, which I assume were 1745.
> 
> Pull weight at 30 inches - 19 pounds
> Velocity -
> .375 lead ball (75 grains) - 192 fps avg 5 shots
> .429 lead ball (115) grains - 182 fps avg 5 shots
> .495 lead ball (175 grains) - 161 fps avg 5 shots
> Note: all measurements were made with my computer and Audacity. Later I will compare the computer measurements against my Chrony.
> * Velocity measured at my normal 34 inches draw.
> 
> Further testing will be with 1842 because that is what I have.
> 
> Now I'm going outside to make some Chrony measurements.


Henry, what are the length of the tubes per side that are being tested?


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## Performance Catapults

timdix said:


> ...The real kicker is that the tubes are so easy to cut and change not to mention cheap(if you're just changing the single strand component).


...and, they are quiet.


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## NaturalFork

Those tubes are super fast. Getting that kind of FPS with such little effort makes them extremely worthwhile. We all appreciate your findings Henry!


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## Henry the Hermit

Rayshot said:


> I've owned a Dankung Jungle Hunter II for more than a year. Right up front, I'll say I don't like the Dankung, but I do like the thin Chinese tubes. I plan to test a variety of configurations, and will use the Dankung because of the ease of changing tubes. To kick things off, here are the results I got from the original OEM bandset, which I assume were 1745.
> 
> Pull weight at 30 inches - 19 pounds
> Velocity -
> .375 lead ball (75 grains) - 192 fps avg 5 shots
> .429 lead ball (115) grains - 182 fps avg 5 shots
> .495 lead ball (175 grains) - 161 fps avg 5 shots
> Note: all measurements were made with my computer and Audacity. Later I will compare the computer measurements against my Chrony.
> * Velocity measured at my normal 34 inches draw.
> 
> Further testing will be with 1842 because that is what I have.
> 
> Now I'm going outside to make some Chrony measurements.


Henry, what are the length of the tubes per side that are being tested?
[/quote]

The double set is 7 inches, the "single" (more about its construction later) is 7.5. That is one of the variables I intend to explore. What is the optimum length for me? Once I determine that, we should be able to take a person's draw length and calculate the optimum for him/her.


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## Henry the Hermit

Yes indeed, they are quiet, and handslap is non-existant, even with .25 steel.

This morning I will be trying .177 BBs, but have to make an ultralight pouch first. My theory, which may be wacko (we shall see), is that if we reduce the weight of the projectile and pouch as much as possible, we can then measure how fast the bands are capable of retracting, and then know the absolute maximum speed of those bands.

OK, here are my results with the looped singles. First a picture of the bands.









The loops measure 2.5 inches (6.35 cm) and the single portion is 5.0 inches (12.7 cm). The pull weight is 8.9 pounds at 32 inches. This is the first round. I have since achieved higher velocities by increasing my draw length. (See post above)

Velocities

.25 cal (6.35mm) steel - 282.8 fps - 2.88 lbs/ft energy.
.304 lead (7.7mm) - 255 fps - 6.0 lbs/ft energy *
.363 lead (9.2mm) - 211.4 - 7.04 lbs/ft energy *
.429 LEAD (10.9MM) - 177.54 - 8.18 lbs/ft **

* These two rounds were real eye openers. Not only is the velocity with .363 almost exactly the same as with the double set (212.4), the .304 is actually faster with the single bands, at roughly half the draw weight. (8.9 vs 15.8)
** The bands are obviously overloaded at this projectile weight, losing more than 20 fps to the double set. Even so, the higher energy level indicates that more speed can be achieved with the lighter projectiles. If my theory is correct, we should be able to get close to 300 fps with .304 lead and somewhat over that with .25 steel.

I'm going to bite the bullet and pay the price for 70 3/8 steel balls, since that is what almost everyone uses. Why don't you guys all switch to lead and save me 5 bucks?


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## Performance Catapults

Henry in Panama said:


> The double set is 7 inches... That is one of the variables I intend to explore. What is the optimum length for me? Once I determine that, we should be able to take a person's draw length and calculate the optimum for him/her.


The fastest set I am offering at this point, the GT1842, is 7.25". Reason being, I didn't want anyone to damage their tendons. The GT1842 compares in resistence to the Tex Shooter, Express Double Flats, that I was shooting for the past few years. The pull is slightly heavier, but not so much that it is uncomfortable. Remember, I had stage 3 trigger thumb surgery, so if it was uncomfortable to shoot, I wasn't going to continue.

So, what a coincidence that our band measurements are so close. Some shooters will be able to handle the extra pull weight of 7". My draw is 30", and the GT1842 allows me to shoot comfortably for extended periods, without sacrificing survival saving, kinetic energy.


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## AZshooter

Thanks for taking the time to do the tests, Henry....I like the idea of the single tube with short loop at the fork end to help create a double tapered effect...What would be the best way to tie off the short loop?...constrictor knot...small piece of 1745 tubing...?


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## LVO

So, Henry this is all using a Dankung? We could expect same speeds using that setup with one of Jim's Performance units, or Bill Hays universal fork setup. Sorry for the newbie question, I'm just trying to get easiest draw to send rounds at about 225 fps. 
Appreciate your help.


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## Henry the Hermit

"So, what a coincidence that our band measurements are so close."

Great minds think alike!

"What would be the best way to tie off the short loop?"

I use black waxed string that I buy from my local leather shop. It's roughly the same diameter as the cotton kite string I used to buy, but much stronger.

Now for the good news.

*I did it!!!*









And here are the bands I used. Length of one side 6.5 inches. The loop is just long enough to fit well on the Dankung. BTW, with the amount of shooting I'm doing, the Dankung is just too uncomfortable, so all future tests will be with Mr. Stubby. I've found no difference in performance but a huge difference in comfort.









Now for some BBs.


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## Charles

Those are great results. What temperature were you shooting at, Henry?

Cheers ....... Charles


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## Henry the Hermit

Rugersteel said:


> So, Henry this is all using a Dankung? We could expect same speeds using that setup with one of Jim's Performance units, or Bill Hays universal fork setup. Sorry for the newbie question, I'm just trying to get easiest draw to send rounds at about 225 fps.
> Appreciate your help.


You can use these bands on any frame you can fit them to. As I noted in my last post, I'm retiring the Dankung because I don't like shooting it. I've seen no difference in speed between it and Mr. Stubby.

http://slingshotforum.com/gallery/image/4559-mr-stubby/


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## Henry the Hermit

Charles said:


> Those are great results. What temperature were you shooting at, Henry?
> 
> Cheers ....... Charles


It's 28 C outside right now, Charles. My heartfelt condolences to those of you who are cold.


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## Charles

Henry in Panama said:


> Those are great results. What temperature were you shooting at, Henry?
> 
> Cheers ....... Charles


It's 28 C outside right now, Charles. My heartfelt condolences to those of you who are cold.








[/quote]

It is 5 C here now in Victoria. I am wondering how much of a difference the temperature will make with the tubes ... I know it can have a serious effect on bands. Anyway, I have just ordered a bunch of 1842 tubes from Dankung ... gonna give that stuff a try. High velocity with relatively light pull is a boon for those of us with arthritis.

Cheers ....... Charles


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## NaturalFork

With these speeds it makes me wonder why I continue to cut flats ...


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## pgandy

Many thanks Henry. I had been considering a Dankung. The primary reason for quick change thinking it ideal for the tube bands I’ve been planning on. I had suspicions about the comfort of that frame with high draw forces and you proved me correct. I now plan to order the bands and pouches in within the next couple of weeks and use on my PSs. I even have a new PS1 on order as they fit my hand to a T distributing draw forces well.


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## AZshooter

Mr. Stubby looks like a good solution for the hand cramp problem...Having some chinese frames myself I find it comfoting to build a wood handle onto the metal frame...Dankung sells them already fit with wood handle, but I prefer to make my own....You might try Fimo molded handles, but I guess most craftsmen here have experimented with Fimo clay....


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## Henry the Hermit

It has been a most interesting day. With the same bandset I used in the last reported results, I asked my 34 year old 6'4" son to try a few shots. I'll let the pictures tell the story.

















I am properly humbled.


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## Performance Catapults

Looks like he means business.

I was always intrigued by the dankungs as well. I didn't like always having to re-position the frame in my hand. Hence the SPS.


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## Rayshot

Henry in Panama said:


> It has been a most interesting day. With the same bandset I used in the last reported results, I asked my 34 year old 6'4" son to try a few shots. I'll let the pictures tell the story.
> 
> View attachment 14284
> 
> 
> View attachment 14285
> 
> 
> I am properly humbled.


309 and 364 are with a .177 if I am following your thread, yes?


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## Henry the Hermit

Rayshot said:


> It has been a most interesting day. With the same bandset I used in the last reported results, I asked my 34 year old 6'4" son to try a few shots. I'll let the pictures tell the story.
> 
> View attachment 14284
> 
> 
> View attachment 14285
> 
> 
> I am properly humbled.


309 and 364 are with a .177 if I am following your thread, yes?
[/quote]

No, 309 was with .25 steel as was my son's 364. .177 BBs were a flop. I have now achieved 300+ with .304 lead. More later.


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## Henry the Hermit

I am now as close to the optimum configuration for maximum speed with light ammo as I consider needful and practical. I won't go into all the details of how I arrived at these dimensions, suffice to say I tied a lot of bandsets and made a lot of measurements. With each new set, I would make the looped portion longer and then trim the single portion a half inch at a time until the bands could not be stretched (by me) any further. Almost every set started at an overall length of 8 inches and maxed out at 5 1/2 to 6 inches. Each time I increased the looped portion length, once I had cut back to about 6 1/2 inches, I got velocity increases. There is, of course, a limit.

I have learned that double sets (like those supplied by Dankung may have lower velocity for light ammo than these, which I will call "tapered" for lack of a better term. I settled on a 4:3 ratio of doubled to single with a total length of 7 inches (17.8 cm). There is more velocity available than I achieved with this configuration, but at the expense of short band and pouch life.

If you want to duplicate these, cut the tubes to 11.5 inches (29.2 cm) Loop one end back so that there are 3 1/2 inches of single tube left (loop 8 inches). Clamp the looped end very near the end with a hemostat. I use a bench vise to hold the hemostat. Pre-stretch the loop and tie as close to the hemostat as possible. I use white waxed string and a constrictor knot. Whatever you use make sure the tie is very tight or you may experience slippage. I tie the pouch by feeding 1/2 inch (1.27 cm) through the pouch hole, clamping with the hemostat, lots of pre-stretch and a constrictor knot as close to the pouch as I can. I will post a tutorial on making these soon.

If you use a short draw, you can adjust the dimensions. Just maintain the 4:3 ratio. I'm drawing about 38 inches to get the velocities below. That is 5.4 stretch factor. I thought my draw was 34 inches, but it seems I've gained some arm strength in the last 6 months.

Today's measurements: All listed are 5 shot averages.

.25 cal (6.35mm) steel - 308.7 fps (94.1 ms) 3.44 lbs/ft (4.66 joules)
.304 (7.7mm) lead - 283.3 fps (86.3 ms) 7.43 lbs/ft (10.07 joules)
.375 (9.5mm) steel - 273.7 fps (83.4 ms) * 9.12 lbs/ft (12.36 joules)
.363 (9.2mm) lead - 242 fps (73.76 ms) * 9.25 lbs/ft (12.51 joules)
.429 (10.9mm) lead - 205.5 fps (62.6 ms) 10.98 lbs/ft (14.89 joules)

* Note: the .375 steel weighs 51 grains and the .363 lead weighs 71, which accounts for the smaller lead ball having a lower velocity than the steel.

As we have seen in previous posts, there is more speed to be had from 1842 rubber, but I'm hoping this configuration will be a happy compromise between raw speed and band life. I hope some of you folks will build your own tapered 1842 bands and report your results.

This is not the end of my experiments, but bandsets built to these dimensions will give you a significant increase in velocity over the standard Dankung double sets for ammo lighter than 3/8 lead. I will continue to post results as I get improvements.

Here's Mr. Stubby with the bands installed.


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## Charles

Very nice results, Henry. And well presented too! I am anxiously awaiting my 1842 tubes to give this a try.

Cheers ....... Charles


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## Henry the Hermit

I made a brief side trip into the raw power side of tapered 1842. I wanted to see if I could get 200+ fps with .495 lead balls. I got 222 fps (67.7 ms), 19.96 lbs/ft (26.69 joules). I have no doubt there is more power there, but I'm not strong enough to pull past 32 inches without shaking enough to endanger my Chrony. I'll have my son take a crack at it later. This is Mr. Stubby with the double tapered set.


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## M.J

Oh yeah!!
I find it hard to beat the simplicity, power and long life of a regular set of looped 1842s but I'll be giving this a shot just to see what it's like.
"Mr. Stubby" looks to be a very fine slingshot as well


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## pgandy

Thanks for the information Henry. You have taken much work out of me finding a good starting point. My 1842 is out there somewhere and hopefully will arrive in a few more weeks. My goal is to increase band life while equalling, if not to exceed present power, which while acceptable is not all that great. Your findings make me optimistic. Hopefully this will save money as it costs much to import the Theraband. Advise when your new video is out.


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## Henry the Hermit

M_J said:


> Oh yeah!!
> I find it hard to beat the simplicity, power and long life of a regular set of looped 1842s but I'll be giving this a shot just to see what it's like.
> "Mr. Stubby" looks to be a very fine slingshot as well


Mr. Stubby is a fine shooter. It doesn't show in the pictures, but there is an offset natural palm swell which fits my hand perfectly.

@pgandy - I haven't done any videos, but I will produce a picture tutorial on tying these bands in the next few days.

Back to the double set, I knew the power was there, and my son just proved it. His fastest shot with the double bands and .495 (12.6mm) lead ball was 259.1 fps (79.97 ms) for 26.8 lbs/ft (36.36 joules). He also took a shot at a fallen green coconut. The ball penetrated all the way through the husk and shell and we could hear it rattle inside when we shook it.

His one shot with a 3/8 lead ball was 327.9 fps, but some seriously painful band slap stopped that line of exploration.

My next phase of the project is to count shots with the tapered set to see if they last.


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## nutthrower

say guy's can you give me some info on what you use to aquire you weight of ammo, and your weight in draw. I've been ask to do some of these and can't, also maybe I can also bother you in how to put in photos .... I've got some real uglys to show ya


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## Charles

nut thrower said:


> say guy's can you give me some info on what you use to aquire you weight of ammo, and your weight in draw. I've been ask to do some of these and can't, also maybe I can also bother you in how to put in photos .... I've got some real uglys to show ya


To measure the weight of you ammo, I have not found anything better than this, and it is cheap:

http://www.leevalley.com/en/garden/page.aspx?p=68352&cat=2,40725

To measure draw weight, I use this gizmo:

http://www.leevalley.com/en/garden/page.aspx?p=67613&cat=2,40733,40734,67613

Again, it is cheap and accurate ... just hook the pouch and pull to your draw length ... presto!

Cheers ...... Charles


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## bullseyeben!

Well 330fps with 3/8 lead! Does that out- joule my 338fps with 9mm? Bloody close id say lol, great research mate.., Ben


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## Performance Catapults

Henry in Panama said:


> I made a brief side trip into the raw power side of tapered 1842. I wanted to see if I could get 200+ fps with .495 lead balls. I got 222 fps (67.7 ms), 19.96 lbs/ft (26.69 joules). I have no doubt there is more power there, but I'm not strong enough to pull past 32 inches without shaking enough to endanger my Chrony. I'll have my son take a crack at it later. This is Mr. Stubby with the double tapered set.
> 
> View attachment 14354


Glad you didn't use my pouch with this setup. I doubt it is strong enough to use safely, as it is not intended to be. It is great to see the exporation you are doing with the tubes however.


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## Hrawk

Ben, if you want a cheap set of scales that will do grams and grains, check this one, $12.99 with free delivery in AU.

LINK


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## nutthrower

excellent guys, will look into both items - thanks


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## bullseyeben!

Sweet, cheers mate! Have to get me one of them too...


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## nutthrower

*Henry, I got to tell ya "Mr. Stubby" is just plain coooooool looking - I think at some point I read here how you installed those eye-bolts if ya wouldn't mind going through it again it would be appreciated.......thanks*

*had I knew how efficient those 1842 bands were I would have ordered those too, thanks for your info*


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## pgandy

@Henry the tutorial was what I was referring to.


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## pgandy

nut thrower said:


> say guy's can you give me some info on what you use to aquire you weight of ammo, and your weight in draw. I've been ask to do some of these and can't, also maybe I can also bother you in how to put in photos .... I've got some real uglys to show ya


This is what I use for draw weight. 
http://www.amazon.co...s00_i00_details
Check here for something to weigh your ammo.
http://www.amazon.co...Scale&x=15&y=15


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## timdix

My 1842 has arrived...squeezed in some brief testing today and it didn't disappoint.
In 29C temp,3/8 steel with a loop then single to give a 2:1 taper,10.5inch long,55-60inch draw: *10 shots averaged 306.3fps,maximum 314.4fps.*
This setup seems absolutely perfect for 3/8 steel,more so than 1745.
The 1745 is just as fast but is much harder on my elbow.Thus my choice for such light ammo would be a no brainer. I expect tube life will be shorter than with1745 but I'm hoping it should still be superior to flats.
The 1745 is probably ideally suited to 3/8 lead and slightly heavier.
A trial with a 5.5 inches of 2050 joined to 5.5 inches of 1842 was a let down.


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## Alex Jacob

Many thanks for sharing all your findings, Henry. May the gods of Up-For-It smile upon you.

My favourite catty, Yellowhammer, is a stubby tree-fork with eye-bolts and is the sweetest shooting catty I've come across. Which is why I only have one other as a spare. I like office bands for the simplicity but the best ones are hard to find here. Going to get a big pile of 1842 now.


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## Dayhiker

Henry, thank you for doing this research. Your writing and presentation are superb! I haven't shot my Jungle Hunter in a year or more for the same reasons. I am now going to make a wooden handle for it and start doing my own experimenting with the 1842's to find my own sweet spot.

Thanks again for all this good info.


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## Henry the Hermit

Performance Catapults said:


> I made a brief side trip into the raw power side of tapered 1842. I wanted to see if I could get 200+ fps with .495 lead balls. I got 222 fps (67.7 ms), 19.96 lbs/ft (26.69 joules). I have no doubt there is more power there, but I'm not strong enough to pull past 32 inches without shaking enough to endanger my Chrony. I'll have my son take a crack at it later. This is Mr. Stubby with the double tapered set.
> 
> View attachment 14354


Glad you didn't use my pouch with this setup. I doubt it is strong enough to use safely, as it is not intended to be. It is great to see the exporation you are doing with the tubes however.








[/quote]

JIm, there is no better pouch on the market for its intended use.They last just about forever, and are the perfect size for 3/8 ammo. I love them, but I noticed when I got into the 300 fps range that they tended to wear faster, so I went with some thicker shoe leather for the power bands.

I'll take this opportunity to caution everyone about powerful slingshots. Everything has to be up to the task. Make sure the fork is strong enough and comfortable to hold. Make sure you can hold onto it when you release. Inspect everything often, and especially, wear good eye protection. Also, if you are experiencing frequent fork hits, fix that problem before you explore high power.


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## Henry the Hermit

bullseyeben! said:


> Well 330fps with 3/8 lead! Does that out- joule my 338fps with 9mm? Bloody close id say lol, great research mate.., Ben


The 3/8 balls I'm using now are 9.2 mm and weigh 71 grains, so if you're using steel, I have the edge. If yours are lead, it's very close.


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## Henry the Hermit

nut thrower said:


> *Henry, I got to tell ya "Mr. Stubby" is just plain coooooool looking - I think at some point I read here how you installed those eye-bolts if ya wouldn't mind going through it again it would be appreciated.......thanks*
> 
> *had I knew how efficient those 1842 bands were I would have ordered those too, thanks for your info*


I used steel eye bolts 3 inches long. I drilled a hole in each fork 2 inches deep, the length of the . The hole is sized so that the bolts screw in with very little force. Then I forced as much 2 part epoxy as i could down the holes and coated the threads on the eye bolts with it. I screwed the bolts in and gave it 24 hours to cure. It is very important not to make the holes too small as that would put radial force from the inside on the forks and the last thing you want is a steel eye bolt hitting you in the face. I tested the eyes by applying 50 pounds of pull with a rope and my fish scale.


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## Henry the Hermit

The tutorial is now up on my website. Here is a direct link so you don't have to look at the commercial stuff.

http://oldpeddler.com/biombos/how-to/bandset-1842/


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## Henry the Hermit

There is now a dedicated forum for bands and tubes. I have moved this topic there.


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## Henry the Hermit

Not surprisingly, the first set of bands on which I kept count failed at 189 shots. I say not surprisingly because most of the shots with that set were drawn to the max. The right side band broke just behind the single side of the loop tie. I've now started shot counts on a new set that has not been abused, shooting at about 240 fps.

I'm also building a cousin to "Mr. Stubby" to keep a shot count on a short loop version. I would appreciate it if the rest of you who are using 1842s would let us know what kind of life you get out of them.


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## Rayshot

Henry in Panama said:


> The tutorial is now up on my website. Here is a direct link so you don't have to look at the commercial stuff.
> 
> http://oldpeddler.co...o/bandset-1842/


Henry, *Marvelous* job on the tutorial!!

I have been following this thread and I appreciate the time, experimentation and sharing you have done.

These tutorials are so good for the newbies to have posted as a "sticky". When I first came to this site there was not the dedicated places to find tutorials like this. This is the best stuff...even for us that have been around.

Note: Edited by Henry to change link.


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## AZshooter

Henry...With a possible problem at the loop connection could it be that the constrictor knot is creating an unusual amount of stress at this point...Would it help to use a bit of contact cement here ( at the connection ), allow it to dry then attach the connection ( with pressure ) ...Over this adding a short section of 1745 tubing...?


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## pgandy

Thanks again Henry. I appreciate your efforts and time in this project and I am sure it will be helpful to many. Approximately how much force are you applying when stretching the bands during fabrication?


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## Henry the Hermit

AZ shooter said:


> Henry...With a possible problem at the loop connection could it be that the constrictor knot is creating an unusual amount of stress at this point...Would it help to use a bit of contact cement here ( at the connection ), allow it to dry then attach the connection ( with pressure ) ...Over this adding a short section of 1745 tubing...?


I have my doubts that this is a solvable problem, but the contact glue is worth a try. A common characteristic of approaching the upper limits of performance is short band life. Please elaborate on the short section of 1745 addition.


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## Henry the Hermit

pgandy said:


> Thanks again Henry. I appreciate your efforts and time in this project and I am sure it will be helpful go many. Approximately how much force are you applying when stretching the bands during fabrication?


I stretch them to near maximum, about 5 times relaxed length. The next time I make a set I will measure the force.


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## AZshooter

Henry...What I meant about adding the short piece of 1745, was to actually fit ( with narrow pliers ) a 1/4 inch ( or slightly shorter ) section over the area where the loop connects...Neil was doing this type of surgery in the construction of his fixed tubes on his Trophy slingshot...With the contact cemented area under this extra layer of tube, this should make a good connection with less severe stress on the connection point...If it were really necessary you could fix a constrictor knot over this 1/4 inch section of 1745, but I personally would try to avoid to much stress at this point...When I learn how to use this #@%"# computer I`ll try to be more articulate in my explanations ( I might even take a few shots with my #@%"# digital camera if I can learn how to get it on the forum display )...


----------



## Henry the Hermit

AZ shooter said:


> Henry...What I meant about adding the short piece of 1745, was to actually fit ( with narrow pliers ) a 1/4 inch ( or slightly shorter ) section over the area where the loop connects...Neil was doing this type of surgery in the construction of his fixed tubes on his Trophy slingshot...With the contact cemented area under this extra layer of tube, this should make a good connection with less severe stress on the connection point...If it were really necessary you could fix a constrictor knot over this 1/4 inch section of 1745, but I personally would try to avoid to much stress at this point...When I learn how to use this #@%"# computer I`ll try to be more articulate in my explanations ( I might even take a few shots with my #@%"# digital camera if I can learn how to get it on the forum display )...


OK, I got it. That is the method I use to tie my Theraband tubes and I tried it on the tapered #107s. I'll have to try to figure out a way to expand the reinforcing tube. Maybe the tips ends of my Circlip pliers will work.


----------



## AZshooter

Henry...Circlip pliers would be the best choice...I forgot to mention that in Chinese tutorials they would sometimes create a small knot on the end of the tube...When the end of the tube is looped around and secured this might add a little more "grab" when you place the small 1/4inch section of 1745 over it...The knot is made with thread...Thanks again for your ambitious research...


----------



## Henry the Hermit

I completed the second longevity test yesterday. Using the 4:3 7 inch long bands, and anchoring below my ear, the right side band broke at the pouch at 355 shots. I retied and got 98 more shots before it broke near the loop tie. Total 453 shots. The shorter draw (28 inches) gave consistent 205-210 fps with 3/8 steel. My son grabbed the slingshot and ripped off about a dozen 300+ fps shots and that may have shortened the life a bit. I can't find my pull weight chart at the moment, but when I get back from the store, I'll redo the pulls of this configuration vs the standard double. I do know that the 3:4 setup has lighter draw and higher velocity than the standard double set.


----------



## alfshooter

Thank you very much, Mr. Henry great information and input from peers fantastic, I learned a lot.
greeting


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## Alex Jacob

Blinking flip, mother! This formula works a treat. I've tried a few dimensions either side but 4:3 inches gives a smooth, accurate and fast shot. Should be as it's fairly close to the golden ratio, which would be about 4.3:2.7 for a 7 inch brace height.

I found I had to really strangle the tubes to avoid slippage though. I tried tying the loops with bowlines but getting them the same length is as tricksy as Bagginses. I've settled on a small overhand knot in the tubing to stop the twine from slipping and it's working fine so far.


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## qute10

Any chance of those draw weights henry?


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## pgandy

[sub]I got my first 1745 rubber yesterday. I still haven't completely explored the 1842 putting it on hold until I could get more 1842. Being satisfied with the results of the 1842 I decided to save what I had left until I could replace what I had used before more experimentation. I have more enroute out there somewhere. [/sub]
[sub]As for the 1745 I like it and find it more powerful than the 1842. I found one 1745 band set that gave the same energy as the 1842 that I use for general purpose. As a comparison; the difference was that I was stretching the 1745 388% vs the 1842's 517%, leaving me to believe longer band life and less expense. The trade off is 21# pull vs 15.5#. I consider the 21# pull good PT. When stepping it up to about 25# I zipped hex nuts through tin cans with no problem. One can is pictured below.[/sub]
[sub]That is about max for me and I don't care to shoot it many times. I can pull more but the fool frame of that Dankung bites into my hand. Also I began having trouble holding on to the pouch and needed large balls or double hex nuts. Perhaps in time I can build those finger muscles up. [/sub]
[sub]The Dankung is now my most used slingshot, but only because of the way it carries. And I like the quick band change ability. Having said that I feel that I should say: My PS slingshots will out shoot it and are more of a pleasure t shoot. They certainly shoot smoother. I get the same accuracy at 40' with my PSs as I do at 30' with the Dankung. I get the same power with the PSs as I do using the Dankung with several band sets requiring 18-19# pull compared to Dankung at 25#. I think that I haven't found the right Dankung formula yet. Band life is shorter with the PS in the upper ranges though. After wearing the second hole in my pocket with a PS I started leaving them home in favour of the Dankung that I can easily conceal under my shirt. For an afternoon of shooting fun the PS has it beat, hands down in my book. [/sub]
[sub]






[/sub]


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## pgandy

Here's a photo of a coconut made after the above post with the 1745. One shot nearly halved it. And I haven't reached its maximum potential yet.


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## Henry the Hermit

pgandy said:


> Here's a photo of a coconut made after the above post with the 1745. One shot nearly halved it. And I haven't reached its maximum potential yet.
> View attachment 15962


No surprise there. My son put a .50 cal lead ball through the husk and shell of a green coconut with double 4:3 taper 1842s.


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## Henry the Hermit

qute10 said:


> Any chance of those draw weights henry?


Sorry I took so long. 4 strand 1842 pulls 16.5 pounds at 32 inches. I have to make up some more 4:3 sets.


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## qute10

Thanks henry be interesting to compare the 4/3 draws to the 10mm multi strand pseudo tapers (tbg) that i am currently obsessing about.


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## Henry the Hermit

4:3 1842 pull weight = 10 pounds 1 ounce at 32 inches.


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## qute10

Wonderful thankyou henry its too cold to chrony here at the moment and i havent rigged up ir leds to chrony inside yet but have great hopes for these 10mm multis very smooth and feel/SOUND fast by comparison to my own dankung tubed 4:3 setups.Mine run at 12.7 but i think they are 1745s (cant get 1842 at a reasonable price at the moment without going to dankung anyhow).


----------



## Alex Jacob

If 1842 tubing is potentially faster than 1745, how does it compare to 2040? I've been using this for straights (simple loops), cos there's less hand-slap than with 1842 and keeping the 1842 for tapers.


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## Henry the Hermit

Alex Jacob said:


> If 1842 tubing is potentially faster than 1745, how does it compare to 2040? I've been using this for straights (simple loops), cos there's less hand-slap than with 1842 and keeping the 1842 for tapers.


If you're getting hand slap, you need heavier ammo or a different frame. I was a bit disappointed with early tests of 2040. I expected more velocity with light ammo, but actually get a bit less than with 1842. Maybe I did something wrong. I still have almost 10 meters of 2040, so plan to do some more experimenting.


----------



## Henry the Hermit

I think I have discovered the reason my bands are breaking at the tie points. I use hemostats to clamp the tubes while I stretch and tie them. I finally (yeah, I'm a little slow.) noticed that the edges of the hemostat jaws are a bit sharp. I now have covered the jaws of a small set with 2040 tubes and will see if that resolves the problem.


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## August West

Henry, mine are breaking in the same place, right in front of the tie. I use hemostats as well, I will try the tubing too and see if it helps. Thanks, Chris


----------



## Henry the Hermit

August West said:


> Henry, mine are breaking in the same place, right in front of the tie. I use hemostats as well, I will try the tubing too and see if it helps. Thanks, Chris


Chris, today I used a very skinny hemostat to put an 1842 sleeve on the tie point. I'm hoping that will protect the tie from the string. Not my idea, just following up on a suggestion made earlier.


----------



## August West

Right now I am trying something a bit different to see if I can improve the longevity. I am using a closed loop chained to a double loop to try still have the tapered effect. I have went down to 20/40 tubes since I am doubling them, so far it seems to be working well but I am not that many shots in. Chris


----------



## Alex Jacob

2040 plain loops are what I use as backup to the 1842 tapers as both handle M8 hex nuts nicely. When it's a bit warmer I'll get some casting kit and brew up some .36 and .50 ammunition (cheers Charles for the buckshot mould - as we limeys spell it - info) then it's back to testing various tube sets.

To stretch the bands prior to tying, I've been using a couple of strong tarp clamps strapped to my knees (in lieu of morris dancing bells for 'tis all great folly). Not my idea - cribbed it off a youtube vid but can't remember who's. I've filed off the jaws a bit and put a layer of gaffa/duct/Jesus tape on the end. The clamps aren't themselves strong enough so I put a ring of low-stretch cord around them and pull via that. Doing so tightens the jaws.

It works well enough and only cost a few bob and a couple of minutes to assemble but the elegant solution would be a jig like the one I saw on another vid I can't find again. It consists of two spring-loaded doors and posts which wedge shut against the pull of the bands. A couple of yacht cam cleats on a board might do the same thing.


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## August West

Henry,
How are your longevity tests going? I have started using cuffs of 17/45 with my constrictor knot directly on top with no prestretch. Been shooting this set up for 3 days or so and so far am really liking it, I have had zero slipping, I haven't been keeping count of my shots but I am still on the original set and have been shooting pretty heavy, so far so good. Chris


----------



## Henry the Hermit

August West said:


> Henry,
> How are your longevity tests going? I have started using cuffs of 17/45 with my constrictor knot directly on top with no prestretch. Been shooting this set up for 3 days or so and so far am really liking it, I have had zero slipping, I haven't been keeping count of my shots but I am still on the original set and have been shooting pretty heavy, so far so good. Chris


I got kinda side-tracked into power bands for a week or so, but I have one set of single 2040 that I use with .30 lead and it has several hundred shots on it. I get a very consistent 200 fps with an ear anchor with this combo. I have not started testing the pseudo-taper 1842 set with cuffs yet.


----------



## Henry the Hermit

Here are some of the results of yesterday's testing. I shot single 2040 and 1842 tube sets in several sizes of ammo. I also shot pseudo tapered and doubled 1842 sets, but won't post those results until I have done the same with 2040. I shot a series at each weight over the Chrony first at 30 inch anchored pull and then at my maximum pull of about 39 inches. I did not test 1745 tubes because I don't like the way they feel, and I get all the speed I need with the softer tubes. Here are the first results.

.30 cal lead ball (39.7 grains)*
2040 single - at 30 inch pull, average velocity 208.80 fps, at full draw 254.95 fps
1842 single - at 30 inch pull, average velocity 202.88 fps, at full draw 247.93 fps
_Interesting to note that at this ammo weight, 2040 is faster than 1842._

.363 cal lead (74 grains)*
2040 single - at 30 inch pull, average velocity 176.80 fps, at full draw 214.83 fps
1842 single - at 30 inch pull, average velocity 188.12 fps, at full draw 216.48 fps
_At this weight, the heavier bands work better. I plan to shoot some 3/8 steel later today and am betting that performance is nearly identical at that weight (53 grains)_

*Note - I weighed 5 balls and divided by five to get an average weight.

Here's a picture of the band sets, 2040 at the top.


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## Charles

Hey, Henry. Thanks for these results ... very useful as always. I am wondering how those tubes handle heavier ammo: .38 lead, .44 lead, even .50 lead. How badly does the velocity deteriorate with increasing mass of the projectile?

Cheers ..... Charles


----------



## Henry the Hermit

Charles said:


> Hey, Henry. Thanks for these results ... very useful as always. I am wondering how those tubes handle heavier ammo: .38 lead, .44 lead, even .50 lead. How badly does the velocity deteriorate with increasing mass of the projectile?
> 
> Cheers ..... Charles


I'll get to that, Charles, but here's a teaser. I'm seeing 197 fps average with pseudo taper 1842 and .429 lead ball at full draw.

Today's results with 3/8 steel (53 grains)
2040 single - at 30 inch pull, average velocity 205.30 fps, at full draw 239.58 fps
1842 single - at 30 inch pull, average velocity 203.87 fps, at full draw 243.93 fps
_These results are so close that I believe this projectile weight is very close to the crossing point where 1842 becomes more efficient than 2040._


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## Charles

Thanks, Henry. I look forward to your results. I like to shoot the heavier stuff.

I think you are right that the 3/8 steel looks like the cross over point for 1842 and 2040.

Can you remind me what the slack length of those bands is ... from pouch tie to the end of the loop?

Cheers ..... Charles


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## Henry the Hermit

Charles said:


> Thanks, Henry. I look forward to your results. I like to shoot the heavier stuff.
> 
> I think you are right that the 3/8 steel looks like the cross over point for 1842 and 2040.
> 
> Can you remind me what the slack length of those bands is ... from pouch tie to the end of the loop?
> 
> Cheers ..... Charles


Sure thing, 7 1/4 inches.


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## M.J

Chinese tubes always keep me guessing.
I mean, it just doesn't seem possible for a 7.25" single 2040 setup to yield 200 fps drawn to 30". I know from experience that this can be the case though because I changed my anchor and my draw length went from 34" to 31" and I'm almost positive my Performance Catapults tubes are faster now than before.
Tubes definately seem to have a sweet spot in terms of stretch. They're not like Theraband where you stretch them to 700% and they work best.


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## crapshot

some body should compare china tubes loops withtexs small latex tubing he now sells


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## M.J

crapshot said:


> some body should compare china tubes loops withtexs small latex tubing he now sells


I've got some coming. I don't have a chrony but I do have a bunch of ammo and steel cans


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## cheese

interesting


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## Henry the Hermit

Just have a minute before my wife and I leave to drive to the Atlantic coast, but I hit 302.7 fps with pseudo tapered 2040 tubes and .30 lead ball a few minutes ago. More tomorrow.


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## Alex Jacob

Thanks for all the work you're doing on this, Henry. Fascinating stuff. Particularly the equalizing ammo weight.


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## August West

It's been 5 days and I am still shooting the same band set with the cuffs. I'm gonna go ahead and say that pseudo tapers definitely last much longer with the 17/45 cuffs. I used a trick I learned putting bicycle grips on to help put the cuffs on, I used a little dish soap in some water to lubricate the bands. The water will evaporate leaving a tiny bit of soap residue that will really lock everything in place. The only drawback is you have to make your bandsets a couple of days in advance so they can dry, if you don't they will slip for sure. Chris


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## Henry the Hermit

Here are the first set of completed tests, on 2040 and 1842 single tube per side band sets. All tests were made using my Natural Ringshooter #5. The shots labeled 30 inches were using an anchor with my knuckle in the hollow just behind my ear lobe and a slight forward tilt to the forks. The full draw shots were simply pulling the bands as far as I could.

I started the tests with .30 caliber (7.6mm) lead balls weighing 39.7 grains, and used increasingly heavy ammo until the power started decreasing. With these two band sets, peak power of 10.43 lb/ft (14.1 joules) was reached with a 125 grain .429 (11mm) cal lead ball at 194 fps. Maximum recorded velocity was 256.7 fps with 2040 and .30 cal lead. The chart below shows averages.

I don't know about you guys, but I am astonished at how much power I got out of such skinny tubes.


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## Charles

Great info, Henry ... Thanks!

Cheers .... Charles


----------



## Henry the Hermit

Charles said:


> Great info, Henry ... Thanks!
> 
> Cheers .... Charles


Hey Charles, just so you will know where this is headed, I just fired a test shot with a 285 grain sinker at 168.4 fps for 18 lb/ft energy using the standard loop configuration of 1842. I plan to go all the way up to 500 grains when I get to 4 tube sets.


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## Charles

I find it interesting that the energy of both sorts of tubes, and both types of draw, began to drop off at the same weight of ammo. I would have expected a bit more variation. I am anxious to see your results for the heavier stuff.

Cheers ..... Charles


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## pgandy

Henry those results closely approximate what I recorded with a 31" draw. The 2040 was on my want list, but after reviewing your results I'll save the money. Thanks.
Henry's
.30 Pb-3.62 fpe 
.375 steel-4.89 
.36 Pb-5.81 
.429 Pb-6.53 
Mine
.31 Pb-3.72 fpe
.375 steel-4.97 fpe
.375 Pb-5.83 fpe
.429 Pb-6.43 fpe

I had the comparison in side by side columns but the forum skewed them badly.


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## Henry the Hermit

pgandy said:


> Henry those results closely approximate what I recorded with a 31" draw. The 2040 was on my want list, but after reviewing your results I'll save the money. Thanks.
> 
> Henry's Mine
> .30 Pb-3.62 fpe .31 Pb-3.72 fpe
> .375 steel-4.89 .375 steel-4.97 fpe
> .36 Pb-5.81 .375 Pb-5.83 fpe
> .429 Pb-6.53 .429 Pb-6.43 fpe


At the lighter pull weights, there is little reason to purchase either if you already have one size. The 2040 is a bit easier to draw. Some people may find one preferable to the other, but it isn't until we get into the heavier pull weights and heavier projectiles that I'm finding any significant difference between 1842 and 2040 tubes. I hope to have the numbers completed for pseudo-tapered sets tomorrow.

Thanks for posting your results.


----------



## Henry the Hermit

Here are the completed tests on 2040 and 1842 pseudo-taper band sets, same methods as in previous post.

Again, I started the tests with .30 caliber (7.6mm) lead balls weighing 39.7 grains, and used increasingly heavy ammo until the power started decreasing. Note that with the 1842 set at full draw, there was still a slight power increase with .495 ball, but since there was a decrease at 30 inch pull, I stopped at that weight.

Peak power of 12.46 lb/ft (16.9 joules) was reached with a 125 grain .429 (11mm) cal lead ball at 212 fps. Maximum recorded velocity was 302.7 fps with 2040 and .30 cal lead. The chart below shows averages.









_Edited to correct graphic._


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## Henry the Hermit

As an aside, my first set of 2040 pseudo-tapers, assembled using the cuff method and my cushioned jaws hemostat, failed at 625 shots by breaking at the pouch. I retied and will see how long they last. The retie only reduced length by about 1/2 inch.


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## Charles

Thanks again for posting these results, Henry. Any idea what the weight of that .357 bullet is?

Cheers ........ Charles


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## Henry the Hermit

Charles said:


> Thanks again for posting these results, Henry. Any idea what the weight of that .357 bullet is?
> 
> Cheers ........ Charles


Sorry about that. I forgot to include the weights on the chart. 161 grains. I have corrected the chart to show weight of .357 and .495.


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## pgandy

Henry this is where we differ. Also I would, for clarity's sake, like to make it clear that I am using one strand per side of 1842 with both ends tied to pouch. There seems to be little difference with lighter ammo. The real difference occurred with .50 cal. lead, as no doubt my larger double hex nuts that weigh 8.2 gm and .50 steel at 8.4 gm will measure also. I am getting 7.47 fpe with .50 cal. steel, about what you are getting with the lead. Those large double hex nuts w/star washer gave 7.51 fpe. With .50 cal. lead I get 8.53 fpe. Draw is 31".

Thinking back on it I tested the pseudo-taper and was disappointed with the results using the 1842 tube as I got more energy with the present, conventional set up. The only ammo that I tried was the .50 lead as I generally shoot heavier ammo. After the initial tests using .50 ammo I decided on the present set up, which measures 6" from pouch, and when time permitted I went back and tested with the lighter ammo. It appears the difference between the two configurations is more pronounced with heavier ammo. From what I've seen the 1745 tubes have about parallel results. With the pseudo-taper and .50. cal. lead I get 9.13 fpe vs 9.88 with a full loop using 1745. The trade off is the tapered band pulls about 6# less and has a slightly softer release, obviously more enjoyable to shoot. The 1842 also has an easier pull, softer release, with less energy in the upper regions. I have more 1745 coming, and the new 1842 is waiting to be cleared by customs. After which I hope to do more testing. From what I've observed and reading between the lines the thin tubes are better adapted to lighter ammo. There is a thread originating in China stating that in China they use 8mm ball with 1745 tubes. My Chinese slingshots all came with about ½ dozen steel 8mm balls.


----------



## Henry the Hermit

pgandy said:


> Henry this is where we differ. Also I would, for clarity's sake, like to make it clear that I am using one strand per side of 1842 with both ends tied to pouch. There seems to be little difference with lighter ammo. The real difference occurred with .50 cal. lead, as no doubt my larger double hex nuts that weigh 8.2 gm and .50 steel at 8.4 gm will measure also. I am getting 7.47 fpe with .50 cal. steel, about what you are getting with the lead. Those large double hex nuts w/star washer gave 7.51 fpe. With .50 cal. lead I get 8.53 fpe. Draw is 31".
> 
> Thinking back on it I tested the pseudo-taper and was disappointed with the results using the 1842 tube as I got more energy with the present, conventional set up. The only ammo that I tried was the .50 lead as I generally shoot heavier ammo. After the initial tests using .50 ammo I decided on the present set up, which measures 6" from pouch, and when time permitted I went back and tested with the lighter ammo. It appears the difference between the two configurations is more pronounced with heavier ammo. From what I've seen the 1745 tubes have about parallel results. With the pseudo-taper and .50. cal. lead I get 9.13 fpe vs 9.88 with a full loop using 1745. The trade off is the tapered band pulls about 6# less and has a slightly softer release, obviously more enjoyable to shoot. The 1842 also has an easier pull, softer release, with less energy in the upper regions. I have more 1745 coming, and the new 1842 is waiting to be cleared by customs. After which I hope to do more testing. From what I've observed and reading between the lines the thin tubes are better adapted to lighter ammo. There is a thread originating in China stating that in China they use 8mm ball with 1745 tubes. My Chinese slingshots all came with about ½ dozen steel 8mm balls.


We may be comparing apples and oranges.. I haven't posted results with the configuration you describe, what I call double tubes, i.e. one long loop with the ends tied at the pouch, or the standard Dankung configuration. My bands are longer than yours, and I haven't made any tests with 1745. I did get 10.7 lb/ft with .495 lead and standard configuration 1842 at 30 inch pull, though, so I don't think our results are going to be that far off. I haven't posted those results yet because I need better ammo than the bank sinkers I've been using. I only tested up to 205 grains so far with standard configuration and power was still climbing.


----------



## Henry the Hermit

Here are the results of tests on the standard Dankung configuration, i.e. one long tube, looped, with both ends tied at the pouch. This chart clearly shows that at the lighter projectile weights, 2040 is more powerful than 1842. Somewhere between 161 grains and 173 grains, 1842 takes the lead. These figures represent velocities ranging from a high of 267 fps to a low of 119 fps. As a matter of interest, I recorded 302.7 fps with the same .30 cal ball and a pseudo taper 2040 set, proving that more is not always better.
Maximum recorded power was 17.17 lb/ft.

Unfortunately, I was unable to find any ammo that weighs 250 grains, so the jump from 205 to 308 is a bit more than I would have liked. Once all my tests are complete, I will make them available. I still have two more band configurations to test.


----------



## pgandy

Thanks Henry. What were your band lengths?


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## Henry the Hermit

pgandy said:


> Thanks Henry. What were your band lengths?


7 1/4 inches ring to pouch tie in all cases. Or at least as close to 7 1/4 inches as I could get.


----------



## Henry the Hermit

OK, I know that some of you guys are bored with all the discussion of lb/ft, because velocity is where the glamour is. So here are the results so far, of velocity measurements, from which the energy figures were derived. Note that with 39.7 grain .30 cal lead, pseudo-tapered outperforms looped. The looped configuration doesn't show a clear advantage until projectile weight reaches 125 grains. (.429 lead) I'm guessing that the crossover point is about 100 grains, but don't have any 100 grain ammo.


----------



## August West

IMO this needs to be stickied, great job Henry.

And BTW, I am getting very good life out of my pseudo tapers now using the 17/45 cuff, my first set just failed yesterday and it tore at a random spot not at the tie not too mention it had a LOT of shots on it. Chris


----------



## Henry the Hermit

August West said:


> IMO this needs to be stickied, great job Henry.
> 
> And BTW, I am getting very good life out of my pseudo tapers now using the 17/45 cuff, my first set just failed yesterday and it tore at a random spot not at the tie not too mention it had a LOT of shots on it. Chris


I got over 600 shots out of my last set, and it broke at the pouch. I just cut back a bit and retied. Considering the way I've been abusing bands in these tests, 600+ shots is very good. The cuffs seem to help, but in my case, I think it was the sharp edges of the hemostat I use to clamp while tying. I solved that problem by putting lengths of 1842 on the jaws.


----------



## Charles

Nice results, Henry. I will have more time to study them when I return.

Cheers .... Charles


----------



## JLS:Survival

[sharedmedia=core:attachments:17126]

these are Tex's tubes and my take on the tapered tube setup, I dont have a chrony but these things pack a punch with this setup w/ 3/8 steel. It is very accurate @ 20+ft for me


----------



## Henry the Hermit

JLS:Survival said:


> these are Tex's tubes and my take on the tapered tube setup, I dont have a chrony but these things pack a punch with this setup w/ 3/8 steel. It is very accurate @ 20+ft for me


Nice setup. I really like the fork. In my opinion you are way overpowered for 3/8 steel. Why not try some .45 or .50 lead? I think you can easily exceed 200 fps with those bands and .50 lead.


----------



## Henry the Hermit

I plan to do a separate tutorial on how to optimize band sets for your draw length, but here are the first results using a single strand per side, with a short attachment loop of 2040 tube, cut to allow maximum stretch factor just past my anchored draw (30 inches). The tubes including loop are 6 1/4 inches ring to pouch tie.


----------



## M.J

I was wondering if that would come up. You wouldn't cut Theraband Gold ann Black the same way so it makes sense that you wouldn't cut 1842 and 2040 the same way either.
Thanks for all the hard work, Henry!


----------



## JLS:Survival

Henry in Panama said:


> these are Tex's tubes and my take on the tapered tube setup, I dont have a chrony but these things pack a punch with this setup w/ 3/8 steel. It is very accurate @ 20+ft for me


Nice setup. I really like the fork. In my opinion you are way overpowered for 3/8 steel. Why not try some .45 or .50 lead? I think you can easily exceed 200 fps with those bands and .50 lead.
[/quote]

Thanks for the input Henry, I just have to find/buy some of that larger ammo, looks like you've been hard at work to


----------



## pgandy

Thanks again Henry. It seems like I am always thanking you, this time for the coming tutorial on optimizing and lengths. I like 1842 and will be using it for sometime to come, but in the full loop fashion. It looks like 1745 will edge it out for me in the long run and perhaps your tutorial will give a clue and save some hard to come by rubber. With the 1745 I definitely will be using your pseudo-taper. I get slightly more energy (it seems like I am an odd ball here as I look at energy and not velocity) with the full loop but not enough to add 5 ¾ pounds to the pull. I really thank you for that. And finally, several times I tried posting a table to this forum only to have the forum skew the columns in *.xlsx or *.docx. I will attempt *.png the next time. You have contributed a valuable tool to this community and I am sure this thread will be referred to many times in the years to come.


----------



## Henry the Hermit

pgandy said:


> Thanks again Henry. It seems like I am always thanking you, this time for the coming tutorial on optimizing and lengths. I like 1842 and will be using it for sometime to come, but in the full loop fashion. It looks like 1745 will edge it out for me in the long run and perhaps your tutorial will give a clue and save some hard to come by rubber. With the 1745 I definitely will be using your pseudo-taper. I get slightly more energy (it seems like I am an odd ball here as I look at energy and not velocity) with the full loop but not enough to add 5 ¾ pounds to the pull. I really thank you for that. And finally, several times I tried posting a table to this forum only to have the forum skew the columns in *.xlsx or *.docx. I will attempt *.png the next time. You have contributed a valuable tool to this community and I am sure this thread will be referred to many times in the years to come.


What I do is take a screenshot of the spreadsheet. On my Linux computer, the default is .png. My screen capture program allows me to select part of the screen or all of it, so I just select the part I want to display. I'm sure Windows can do the same, but I'd rather go out in the backyard and eat worms than use Windows.


----------



## Henry the Hermit

My single strand set of 2040 finally broke at the pouch this morning after about 1000 shots. Considering more than half those shots were with the tubes stretched to 90% of absolute max, I think that's not too bad.


----------



## joseph_curwen

very interesting post









i wonder what size should i use for a butterfly set?

Will experiment soon


----------



## Henry the Hermit

joseph_curwen said:


> very interesting post
> 
> 
> 
> 
> 
> 
> 
> 
> 
> i wonder what size should i use for a butterfly set?
> 
> Will experiment soon


I had very disappointing results with butterfly length tubes. I mounted them on a Starship with 54 inch pull and actually got slower speeds. It seems the Chinese tubes work best at short lengths. If you give them a try, please post your results here. Try a 5:1 stretch factor.


----------



## pgandy

I had a most delightful morning thanks to you Henry. I've pretty much shelved my PS and flat bands due to the way a Dankung carries and the longer band life of those small tubes, not to mention the bands are faster to make. I had settled for a full loop of 1842 for practice and general purpose. And a more powerful 1745 pseudo tapered band for carry while looking for something better, both using one tube per side. I have a factory 2040 band w/4 loops (aka 8 strands). It was the most powerful band I have but at 25+# of pull it caused the Dankung to bite uncomfortably into my hand. It took a while but I finally latched on to some 2040 rubber and using from your posts and my experienced I correctly reasoned that I could up the power of that 2040 commercial band while lowering the draw weight and using less rubber by using 4 loops (2 per side) of pseudo tapered 2040. Now that's got to be a winning combination in anybody's book, upping the power with less.

The first band set didn't quite hack it. I used the same dimensions that I had on the 1745 sets forgetting that I'd made them slightly longer ratio than 4/4/3 to increase the life when rubber was in short supply and never changed back. The second set I shortened to that ratio and the band set is all that I had hoped for.

It pulls at 19.5# at 31". With a 33" draw I am getting 12.0 fpe with .50 cal. lead. The ball averages 177.0 fps. I know by the standards of some out there this is not exceptional, but it's significantly better than I've been doing which is 10.2 fpe using the pseudo tapered 1745 at a pound less pull. I'm now pushing .38 lead at 233 fps. This is up from 212 fps. The fpe went from 7.6 to 9.1. The factory 2040 gave me 10.5 fpe with .50 cal. lead. However, at the time I was drawing 31" and am now up to 33". I'm having a ball watching the effects of the extra power. It's too soon to know about band life.


----------



## Charles

I think this is a very important thread, so I have pinned it so that everyone can find it easily.

Cheers ..... Charles


----------



## Henry the Hermit

While it may appear that I have stopped testing and reporting results, that is not correct. 3 days after my last post, I left for Texas on a family emergency and just returned this week. More results next week.

Thanks for the pin, Charles.


----------



## Performance Catapults

The last order I placed for 2040, was four rolls. I received them about three weeks ago. Took them to the ECST, and discovered they were not shooting at all like 2040's should. Normally, I would get about 11# pull weight, but was getting 16# from the order I received. I was struggling to hold a steady draw. Serious hand slaps. I spoke to dankung, and they were initially concerned if I was sure I was shooting 2040. I told them the only thing I can do is take a pic of the ends to show them what I have. Haven't followed through yet, but I will.

I too really like how well the 2040's shoot. Almost 200fps with 3/8" steel, and so easy to draw. I just hope the batch my order came from is gone.


----------



## M.J

Looped 2040s are my favorite.
The set I'm using now starts with a 13" length on each side so after looping and tying I get about 6.25" effective length.
With my 31" draw these will send a 7/16" steel ammo through a free-standing Coke can at 35' so fast that it goes through and almost doesn't knock the can over. I don't have a chrony but that's fast!
Super-smooth and easy draw as well.
That set Jim is talking about with the heavy pull is what I shot my scored targets with at the ECST. They're fast but brutal, even at a longer length. Very unusual for 2040s.


----------



## Charles

Henry in Panama said:


> My single strand set of 2040 finally broke at the pouch this morning after about 1000 shots. Considering more than half those shots were with the tubes stretched to 90% of absolute max, I think that's not too bad.


Just a note of clarification, Henry. Do I understand you correctly that you are using a set up in which each band is a single strand of 2040, not doubled, not half doubled?

Cheers ..... Charles


----------



## Henry the Hermit

Charles said:


> My single strand set of 2040 finally broke at the pouch this morning after about 1000 shots. Considering more than half those shots were with the tubes stretched to 90% of absolute max, I think that's not too bad.


Just a note of clarification, Henry. Do I understand you correctly that you are using a set up in which each band is a single strand of 2040, not doubled, not half doubled?

Cheers ..... Charles
[/quote]

That is correct, Charles. I use 4 different configurations in these tests. The one I call single has a small attachment loop only. I use pseudo-tapered with about half of the tubes looped. I also use a double set of those half looped tubes, and finally a full loop such as Dankung supplies. For the benefit of newcomers who have not read the whole thread, here is a picture of the bandsets, ammo, and Ring Shooter which I am using for the tests. The tapered Theraband Yellow Tube and the double tapered 2040 have not yet been chronyed, but from informal tests I think the TBY will win out because of simplicity and band life. The ammo shown ranges from BBs up to .495 lead ball.


----------



## Performance Catapults

I just tested the pull weight of the two different 2040's. The set with the common pull weight we are accustomed too, has a static loop length of 6 3/4". The pull weight is 10# at 30".

The other set is the 2040 that was delivered on my last order. It has a 1/4" longer static length. Pull weight is 16.5#.

This is the best pic I could take this morning with the low light today. 1842 is on top, with the 2040 below. This is just to demonstrate that I am getting these readings from 2040.


----------



## JetBlack

My dankung came with 8 pc 2040's & I really dont like them. They were a bit short for me, game me bad slaps and tangled a lot. I ordered some bullskin pouches with four holes for tubing and 1745, it is awesome! I punched a hole in the middle and only shoot 7/16 or half inch with them. What a diff in power over 1842 bands.


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## Henry the Hermit

Double Pseudo Tapered 1842.









I'm going to conclude my general velocity tests with this one, The relationship between 1842 and 2040 is well established and I have reached the upper limit of my ability to shoot strong bands. This set pulls over 25 pounds at 32 inches. I also believe there are better alternatives for high power than multiple strands of thin tubes. On the downside, they are a bit tricky to make, and fussy to keep dressed after each shot. Even so, if you have only thin Chinese tube, a double set of pseudo tapered 1745/1842/2040 will absolutely get you into small game hunting power levels.

There are only one set of figures for each ammo weight, because I can only pull this set a couple of inches past my anchor point. Maybe later I'll ask my son to give these a shot.

My latest measurements: All listed are 6 shot averages.

.375 (9.5mm) steel - 285.35 fps - 9.57 lbs/ft
.363 (9.2mm) lead - 267.52 fps - 11.75 lbs/ft
.429 (10.9mm) lead - 239.70 fps - 15.93 lbs/ft
.357 lead bullet - 213.98 fps - 16.35 lbs/ft
.495 (10.9mm) lead - 215.12 fps - 17.76 lbs/ft

Unfortunately, I was unable to properly test this configuration with heavier ammo, because the lead sinkers I have were causing fork hits, but I am confident this set is capable of more than 20 lbs/ft.

Next up, how to maximize tubes for your draw.


----------



## M.J

Henry in Panama said:


> Next up, how to maximize tubes for your draw.


Very much looking forward to that!


----------



## Charles

Keep up the good work, Henry. You are a gem to do all of this.

Cheers ...... Charles


----------



## pgandy

Thanks for all of your work Henry. You certainly opened doors for me. For me, considering my strength, single full looped 1842 is the most enjoyable to shoot with the longest band life. I can get more shots in before fatigue sets in and I am happy with it. My favourite general carry band is 1745 tapered single band although I am beginning to use double 2040. I get more power than with the 1842, carries best in my pocket. And I consider it good for PT. At the moment it is my most used band, probably because I am trying to condition myself for 2040. I get the most power out of 2040 double bands, tapered. It carries well enough in my pocket and is what I carry away from the house these days. I was considering that combination with 1842 rubber although I have reservations. I think I’ve toped out with the 2040 double bands tapered but will have a go with the double 1842 when my new shipment arrives.


----------



## timdix

Always interesting Henry. 
Tested 1842/1745/2050 in tapers last week just to review previous findings. It's getting frigid down under (10C on morning of test) so results were non stellar. 1745's were still clearly in front averaging 300-305fps with 3/8 steels with the long 150cm draw. A good 10fps faster than the 1842 and 2050 2:1 tapers.
I just find 1842's a tad flimsy. An easy draw but they tend to break more rapidly and dramatically ....something you don't want at the mid junction of a tapered rig! 
No denying it though,tapered tubes are a fiddle but get the brew right and they're really punchy.
Henry,can you get you're 6 foot 4 son to try 1745 tapers 17:17cm(34cm total) with 3/8 steel or lead? That'd be scary.


----------



## Henry the Hermit

timdix said:


> Always interesting Henry.
> Tested 1842/1745/2050 in tapers last week just to review previous findings. It's getting frigid down under (10C on morning of test) so results were non stellar. 1745's were still clearly in front averaging 300-305fps with 3/8 steels with the long 150cm draw. A good 10fps faster than the 1842 and 2050 2:1 tapers.
> I just find 1842's a tad flimsy. An easy draw but they tend to break more rapidly and dramatically ....something you don't want at the mid junction of a tapered rig!
> No denying it though,tapered tubes are a fiddle but get the brew right and they're really punchy.
> Henry,can you get you're 6 foot 4 son to try 1745 tapers 17:17cm(34cm total) with 3/8 steel or lead? That'd be scary.


I'm going to have him shoot a few rounds with the double tapered 1842, but I don't have any 1745. Maybe on my next order.


----------



## Northerner

1842 vs 1745... What would be the draw weight difference for 7" loops drawn to 30"-32"?

For comparison, TBG can do 200 fps with 3/8" steel and a 10-11 lb draw weight.

Thanks,
Northerner


----------



## Henry the Hermit

Northerner said:


> 1842 vs 1745... What would be the draw weight difference for 7" loops drawn to 30"-32"?
> 
> For comparison, TBG can do 200 fps with 3/8" steel and a 10-11 lb draw weight.
> 
> Thanks,
> Northerner


My looped 1842 pulls 13 lb 10 oz at 32 inches and averaged 211 fps with 3/8 steel. A better comparison is my pseudo-tapered 1842 at 9 lb 15 oz and 218 fps. That same set averaged 251 fps when stretched out. This in no way implies that Chinese tube is better than TBG, but just FWIW, I have not been able to achieve more than 305 fps with light ammo (BBs and .25 steel) and TBG. I've seen 360+ fps with single 2040 tubes.


----------



## Northerner

Henry in Panama said:


> 1842 vs 1745... What would be the draw weight difference for 7" loops drawn to 30"-32"?
> 
> For comparison, TBG can do 200 fps with 3/8" steel and a 10-11 lb draw weight.
> 
> Thanks,
> Northerner


My looped 1842 pulls 13 lb 10 oz at 32 inches and averaged 211 fps with 3/8 steel. A better comparison is my pseudo-tapered 1842 at 9 lb 15 oz and 218 fps. That same set averaged 251 fps when stretched out. This in no way implies that Chinese tube is better than TBG, but just FWIW, I have not been able to achieve more than 305 fps with light ammo (BBs and .25 steel) and TBG. I've seen 360+ fps with single 2040 tubes.
[/quote]

I just did a chrony check with some fresh .030" Hygenic latex that I bought from Tex. The cut was 15/16 x 3/4" x 7 1/4". At 32" it pulled 12 1/4 lbs and clocked 208 fps with 3/8" steel and a Tex pouch. The .030" latex bands seem to be about the same efficiency as 1842 looped tubes when using 3/8" steel.

Cheers,
Northerner


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## Wingshooter

I set myself up a 1745 single tube setup 61/2 inches. At my draw length I can get between 200 and 214 with 3/8 steel and it draws with your fingertips. I have been shooting 7/16 and still get 185 fps. I used the top slot and folded the tube back over itself locking it in place. On the pouch end I punched a hole in one side of the tube like the RRT's and threaded the tube through itself and that is my pouch setup it works great on these tubes. The pouch is a single layer pigskin. This is a good light duty tube setup and they have long life.


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## DaveSteve

Thanks for sharing. Nice setup. Would work great for my marbles.


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## Rayshot

Wingshooter said:


> I set myself up a 1745 single tube setup 61/2 inches. At my draw length I can get between 200 and 214 with 3/8 steel and it draws with your fingertips. I have been shooting 7/16 and still get 185 fps. I used the top slot and folded the tube back over itself locking it in place. On the pouch end I punched a hole in one side of the tube like the RRT's and threaded the tube through itself and that is my pouch setup it works great on these tubes. The pouch is a single layer pigskin. This is a good light duty tube setup and they have long life.


Unbelievable. Today I did the exact same thing. Single tube of 1745 red tube, 6 1/2 inches, 5/8 inch wide SuperPouch at a 30-31in draw with a slight pause upon full draw letting loose 3/8 steel.......196 to 199 FPS. I shot TTF. When I shoot intuitive my FPS usually would be more like what Roger was getting.


----------



## pop shot

Henry- with the 1842 are you still sticking to a 4:3 ratio? with 4:3 ratio, what was the best elongation you found? is it around 500%? I'm using 3/8 and 7/16 steel. it's hard sifting through this thread, as it's an ongoing experiment, and your methods change/upgrade as it goes on. what's your elongation sweet spot for single 1842?

Steve


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## Henry the Hermit

pop shot said:


> Henry- with the 1842 are you still sticking to a 4:3 ratio? with 4:3 ratio, what was the best elongation you found? is it around 500%? I'm using 3/8 and 7/16 steel. it's hard sifting through this thread, as it's an ongoing experiment, and your methods change/upgrade as it goes on. what's your elongation sweet spot for single 1842?
> 
> Steve


Steve, I make my pseudo tapered with the 4:3 ratio. I have not completed my optimization tests yet, but for maximum power, it looks like 550% is going to be close.

Henry


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## Henry the Hermit

My son just shot a few rounds with the double pseudo tapered 1842 and .495 cal lead. Here is his fastest shot. Unfortunately, the set broke at the loop tie with about 100 shots on it.


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## pop shot

About 46-48" draw? (guessing from his earlier picture)


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## Henry the Hermit

pop shot said:


> About 46-48" draw? (guessing from his earlier picture)


I'd put it closer to 40. He didn't pull this set back as far as the earlier set.


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## timdix

Did some tests today and I got some huge suprises.
Previously I have always used a 1:1 ration 1745 taper giving around 300fps or just over. Today I tried a variation: a 13cm loop to a 17cm single shot butterfly to 150cm+ That gives around a 3:4 ratio...WOW,incredible...with 3/8 steels they were blowing past 300,mostly around 330-340,max of 357fps.This is in winter @ 13C! Was thinking I should crosscheck the chrony!
I'm convinced tapered tubes give a compound bow effect. Having a long single gives the backbone to the speed of the shot. A shorter double gives an acceleration upon an acceleration like a multiplier effect which can give truly remarkable speeds which match super tapered flats.
So the take home message,consider a slightly longer pouch section for maximum performance. The optimum ratio,well that's hard to say.


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## timdix

Did some further readings this morning...only 300-310fps with the 3:4 ratio taper. I think the artificial lighting yesterday was messing with the readings. Even so,I think with the longer single segment it shoots with an easier pull with at least the same speed as a 1:1 taper.


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## bullseyeben!

As I find with tap flats, the wider the fork end cut, the more initial torque the bands have to accelerate the shot, so larger amo required a wider fork end band, whilst pouch end relates to top speed, so a thinner pouch end will get lighter amo top speed.. same I guess with a loop taper: bigger fork end loop: more torque:less top end.. obviously fine tuning is required to what weight ammo is being shot..


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## pgandy

I don't know your chrony nor type of lighting. However, the instructions that came with mine warned about fluorescent lighting.

When it comes to tapered tubes I also am getting better results with 1745 than 1842 with single bands. I can't go a double 1745, but double 2040 and double 1842 will exceed the single 1745 for those interested in more power. My best tubes equal about my best flats and have a longer life. I am now sold on tubes.


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## trobbie66

I would like to thank you Henry. I just bought my first Dankung and roll of tube. This thread has saved me blindly butchering the whole roll to get a set that performs well.I am using a seudo taper and having great results. I might have given up on the whole program if this thread wasn't here to reference. Great job, very informative!!!


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## buckarue

Hi Henry, have you did any test on the durability of the chinese bands?


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## BuBsMuBollock

Hello I would like to thank u all for your time and information given here being a nooby you have helped me and I'm sure many others thanks again Bubs .


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## Henry the Hermit

buckarue said:


> Hi Henry, have you did any test on the durability of the chinese bands?


Yes, longevity was discussed in this Topic, starting on page 2. Briefly, you can expect close to 1,000 shots with a looped configuration at a stretch factor of 5 or less. The more you stretch them, the shorter the life.


----------



## Henry the Hermit

Yesterday, I cut some new 2040 bandsets. I wanted to find what effect different loop-single ratios would have. As expected, longer loops and shorter single sections increased velocity. The surprise came at the 1:1 ratio. Earlier in this series, I settled on a 4:3 loop to single ratio, and had previously achieved 365 fps using a super-light pouch and .25 cal (6.35 mm) steel ammo. I was thrilled to see 377 fps early this morning with the same ammo and a similar pouch. So I got out my tiny Sport Cam and mounted it on my Chrony so you guys can see my ruggedly handsome face, and took a few shots. My new personal speed record is now 380.7 fps.

This bandset is cut for 6.5 inches finished loop to pouch tie dimension and my draw is about 36 inches. The 1:1 ratio makes the math very easy. Decide what relaxed pull length you want, divide by 3 and add 1/2 inch. The extra 1/2 inch is to let you make the pouch tie without shortening the pull length. Then double 2/3 of that and make the loop tie. In my case I had a 3.25 inch loop and a 3.75 inch single section. After tying the pouch, I had 6.5 inches loop to pouch.

Here's a link to a tutorial on how I tie the bandsets. Note that I now place a sleeve over the loop tie point before tying.

http://oldpeddler.co...o/bandset-1842/

Here's my amateurish video.

"http://www.youtube.com/watch?v=sYDdwJ9e_EA&feature=plcp"]


----------



## lightgeoduck

Smokn Henry, Just Smokn

Thanks for sharing the demo vid, and all of the info that you take the time to write up here.

Thanks for do the work for us









LGD


----------



## pop shot

what was this talk about the rugged good looks? all i saw was hemingway shooting a slingshot. 380.7 is insane. 1:1 is the sweet spot, huh?


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## capnjoe

What a mug. 
Those speeds are insane! I never knew. Great thread, Henry.


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## Henry the Hermit

Thanks guys. The speeds are fun, but aside from bragging rights, I'm not too sure what they are good for. It is kinda neat to see a 1/4 inch steel ball punch through a steel can, though. The real speed is with thin flats and full albatross draw. Torsten has exceeded 500 fps. I think 380 is pretty good for regular draw tubes, but I'm shooting for 400. The trick is light bands, light pouches and ties, light ammo, and stretching the rubber as far as it will go.


----------



## Beanflip

That's pretty cool. Thanks for sharing the video. ( we get to know you better with video ) I have a set of tex heavy bands in your taper set up. They rip 44 and 50 cal lead.


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## M.J

Beanflip said:


> That's pretty cool. Thanks for sharing the video. ( we get to know you better with video ) I have a set of tex heavy bands in your taper set up. They rip 44 and 50 cal lead.


I bet those bands in that setup would kill a water buffalo!
I set up some Theratube Yellow in about this same configuration. It has an easy draw but smashes face with 5/8" steel!


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## Beanflip

I never would have tried them with out Henry.


----------



## bullseyeben!

Thats very impressive!


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## tnflipper52

Man, you are shootin laser beams there Henry. Congrats on your 380 fps. I know you had fun making it, and more fun trying to beat it. Thanks for sharing your knowledge and talent with us.


----------



## boby

I've recently gotten back into shooting slingshots again and have followed with interest the discussion on Chinese tubes. As a retired physicist, I have time to try to make sense of the unexpected result that tapered bands (e.g., 4 strand mixed with 2 strand on each side) can outperform single bands (e.g. 2 strands per side). One can algebraically model a slingshot in which each side is composed of 2 strands in series, with each strand having different stiffness, mass, length, etc.. In the simplified case where the draw force is proportional to the amount of draw beyond the unpulled length (="draw length"),_* I did not find any advantage to pseudo tapered bands over untapered at CONSTANT draw length AND pull force;*_ (by untapered, I mean constant band configuration all the way between pouch and slingshot "Y") . This calculation includes the mass of the rubber bands, the variation in velocity along the bands, and the mass of the pouch and projectile.

To get constant draw length and pull force for different types of bands, one needs to change the unstretched length of band(s). It seems that many on this forum are not aware of some general rules that can help understand observations. In particular, the pull force at a given draw can be doubled by doubling the number of identical strands side-by-side (i.e., in parallel) or by HALVING the UNstretched length of all bands. Alternatively, the pull force at a given draw length can be halved by halving the number of bands in parallel or by doubling the UNstretched length of all bands. This means that it is very important to carefully monitor the UNstretched length of bands as this can make more difference in stiffness than the band type (e.g., 2040, 1745, etc.).

I'm not sure why I didn't find it favorable to have pseudo-tapered bands at constant draw length & pull force. It is hard to know what the pull force is, so the various speed measurements that are being reported in this forum are hard to do at constant pull force. Also, if the pull force is reduced by tapering, it becomes easier to pull the pouch back and draw lengths are likely to increase as a result. Projectile speed is pretty sensitive to draw length, so an unplanned extra draw length could be contributing to a perception of higher speed for pseudo-tapered.

For the numerically oriented, the stiffness constants k (which have units of force / "draw length" ) combine in parallel like

k.effective = k1 + k2 (k1 & k2 in parallel),

while in series combine like

1/k.effective = 1/k1 + 1/k2 (k2 added to end of k1 (="series" connection)).

So be sure to report unstretched band lengths, and when possible control draw lengths and measure the force needed to achieve such draw lengths.


----------



## Henry the Hermit

Most of that is so far over my head that I won't even try to reply to it, but I will address one statement.



> an unplanned extra draw length could be contributing to a perception of higher speed for pseudo-tapered.


There is no "perception" of higher speed. The speeds reported were _measured_ with a Chrony. Few of us are interested in theoretical performance. We're looking for what happens in the everyday world. Few of us have or are willing to build special equipment to apply equal force to every shot, every configuration. Such information would be of little use in any case, since we just pull the bands back to a point which can vary depending on angle of shot, clothing, etc. and let go. It is useful to know which configuration will produce the most power or highest speeds. with the minimum draw weight. In every case I tried, the pseudo-taper configuration won handily. It produced the fastest speeds (380 fps) with light ammo and the most power (26+lb/ft - two pseudo-tapers per side) with heavy ammo.

Of course, if you were to do a series of tests and write them up in simple enough language for everybody to understand, I'm sure there would be a lot of interest.


----------



## pgandy

Theroy is theory, which is good within limits. However in real life with my slingshot I find that I am probably the biggest variable, either with my shooting or in making a band set as has been proven with my chrony. Including the variables in shot to shot or band set to band set my chrony tells me that I obtain higher velocity with a pseudo taper than a full loop and my fish scale tells me, as does my arm, that the draw weight is less. I am more inclined to believe my instruments than what should or should not be happening.


----------



## boby

I want to add to the analysis I described yesterday. There I looked at pseudo-tapered vs standard performance at constant pull force AND draw length BEYOND the unstretched length. A more appropriate comparison is at constant pull force and distance between anchor point (e.g. ear) and slingshot frame. This changes the conclusions but with a twist: pseudo-tapered configurations are beneficial over untapered configurations ONLY if the pseudo-taper has LESS band mass than the untapered-- a pseudo-tapered design with more mass than the untapered performs worse than the untapered design at constant pull force and anchor distance. For example, a standard chinese tube configuration for an untapered design has 2 bands on each side. Relative to that, a pseudo-tapered configuration with 1 plus 2 bands on each side gives better performance, while a pseudo-taper with 2 plus 4 bands on each side gives worse performance. This is not a surprise if you measure the various masses because the rubber bands (e.g. for 2040 bands) dominate all masses. E.g., for a typical untapered design, the bands weigh 8g, the pouch 3g, and the 3/8" steel ball weighs 3.5g.

I've included a pdf document that gives some calculation results plus commentary, and the function that calculated them. I am now comfortable that a rather standard physical model gives reasonable results-- and is much more convenient for understanding trends than building & testing different rubber band configurations. You may want to look only at the calculated results, but to understand the symbols used you may want to read the documentation comments at the beginning of the shown function. An example result:

For an anchor length of 30" & with 13.8 lb pull, a 3/8" steel ball has:
pseudo-tapered: 238 ft/s speed & 6.9 ft-lb energy
untapered: 205 ft/s speed & 5.1 ft-lb energy.


----------



## Hrawk

Very nice, keep it up.

My first observation though is that you use a constant for koa - force per inch.

Others and myself have observed that this is not a linear rate.

Also it has been observed that rubber looses it's elasticity the longer it has been drawn out. Joerg S has studied this with the use of a thermal camera. Several members have also recorded slower speeds when the rubber is drawn for a period of time. DUGI demonstrates this quite effectively with his fast draw and shoot technique.


----------



## boby

Hrawk,
I am aware that F=k* DeltaX is an approximattion for rubber bands, and that there is hysteresis etc., but one would hope that it would be sufficient to understand the nature of pseudo-taper benefits or their lack, and I think that now this has been illuminated. By calibrating the rubber elastic (i.e., k) properties by using someone's measured velocity data (as I have done), one is closer to getting the velocity right at the expense of pull force. In any case, pull force is usually not measured carefully, and would depend on how long one holds the draw before releasing (because of the hysteresis effects). If there were more observations of time-dependent pull force and energy lost inelastically in the rubber, one might be able to make better fudge factors to account for these extra complications (perhaps an effective mass for rubber bands greater than the actual value?). From what I have seen in brief google searches, F=k*DeltaX is not off by more than ~25% when hysteresis & nonproportionality are included (except at extreme pulls near the rubber breaking point), so I am not motivated to get heroic about improving the calculations I have used, but if anyone has some practical suggestions, I'm all ears.


----------



## Hrawk

Don't get me wrong man, I think what you are doing is great and those big words are downright sexy









If you need any specific test data let me know. I have a few sets of reasonably accurate pull scales as well chrony etc.


----------



## lightgeoduck

boby,

That is some killer information that you are laying on us.. theories, science and math can be a good read for sure. As far as slingshots I am not an exact science kind of guy, but I do appreciate and find useful what others have put alot of effort in to sharing with the community... "Z" was a very scientific guy when he discussed slingshot theories. Hrawk as well puts up some excellent data information. Just keep in mind the nature of this thread and others of its kind. It gives us a practical image of what everyday shooters could experience with certain set ups. I don:t know the benefits of one or the other, but when I see 380fps coming from someone:s set up and compare it to their tests of other set ups.. it gives me a general idea what to expect when I make my generic adjustments for my shooting set up.

Everything serves its purpose in one way shape or form... and if you are up to the "challenge" it would be nice for you to share your knowledge in a thread/blog with tests and figures combined. It definitely seems you would be a big asset to the community by doing so.


----------



## pgandy

@Boby that explains why my pseudo tapered 2050 gave less performance than a full loop. I figured that I was on the back side of the curve and gave up testing early. 2050 is double the price of 1842 and 1745, and about 4x the 2040 and I wasn’t getting the expected results. I should point out that the factory full 2050 loop and the pseudo taper were from different manufacturers. The tests would have been more meaningful using the same lot. I have enough 2050 left to make a full loop and will go back and retest.


----------



## Henry the Hermit

I'm hoping to set a new personal speed record tomorrow morning. I fiddled a bit with dimensions, increasing overall rubber length to 7.0 inches. This allows me to stretch the set a couple of inches more and should increase velocity. First tests were encouraging. With a cooler temperature and only about 15 shots on the set, I recorded 375 and 377 fps. A few more breakin shots and a warmer temp should get me comfortably over 380 fps. This is with 2040 pseudo taper, 1:1 ratio and .25 inch steel. Total tube set weight with pouch tied is 6.25 grams/ 96.4 grains.


----------



## carbonspy

Yeah, those tubes are quite cheap, from where I buy them, 10 metres are around 4USD.


----------



## LVO

carbonspy said:


> Yeah, those tubes are quite cheap, from where I buy them, 10 metres are around 4USD.


Wow! can you share that site with us?


----------



## Henry the Hermit

2040 tube is $4.90 plus shipping ($2.92 to US) for 10 meters from Dankung.com. I'd like to know where I can get it for half that price, too.


----------



## Henry the Hermit

Tests today were a bit disappointing. I really expected to see over 380 fps, but the best I could muster was a couple of 375+ shots. So, I didn't break my record but I did break a tube, so further tests will have to wait for my Dankung shipment to get here.


----------



## pgandy

LVO said:


> Yeah, those tubes are quite cheap, from where I buy them, 10 metres are around 4USD.


Wow! can you share that site with us?
[/quote]
http://www.dankung.com/emart/index.php?main_page=advanced_search_result&search_in_description=1&keyword=20*40


----------



## Northerner

Does Dankung not use their posted shipping fee?

"The start shipping fee is $16 for THREE items. Therefor you will be charged $16 when you order one,two or three items."


----------



## Henry the Hermit

Northerner said:


> Does Dankung not use their posted shipping fee?
> 
> "The start shipping fee is $16 for THREE items. Therefor you will be charged $16 when you order one,two or three items."


They have two shipping methods. The "per item" method is much cheaper, but a bit slower. They don't do a very good job of advertising it, but if you start the checkout procedure you will be given a chance to compute the shipping. Per item shipping for 2040 is $2.92 for one 10 meter length to my US address.


----------



## Hrawk




----------



## Beanflip

Wow! Did not know that. High shipping has always kept me from ordering. thanks for the info.


----------



## Henry the Hermit

Beanflip said:


> Wow! Did not know that. High shipping has always kept me from ordering. thanks for the info.


If you don't mind the longer delivery time, Dankung is, I believe the cheapest place to buy tubes. Truly Texas has great service and I have had good experience with them, but Dankung's delivered price is a lot cheaper and TT doesn't carry 2040.


----------



## Beanflip

For that price waiting is easy. I ordered some. I love all this slingshot stuff. Hello,my name is ----- and i am a slingshot addict.


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## Hrawk

Hello and welcome. I guess I'm lucky living in Australia, orders from Dankung take on average 5-7 days.


----------



## lightgeoduck

Hrawk said:


> Hello and welcome. I guess I'm lucky living in Australia, orders from Dankung take on average 5-7 days.


 3-5 to japan


----------



## pgandy

Henry in Panama said:


> Wow! Did not know that. High shipping has always kept me from ordering. thanks for the info.


If you don't mind the longer delivery time, Dankung is, I believe the cheapest place to buy tubes. Truly Texas has great service and I have had good experience with them, but Dankung's delivered price is a lot cheaper and TT doesn't carry 2040.
[/quote]

The longer delivery time doesn't bother me either. I just move up the reorder point. The problem I found with Truly Texas two fold. One he misrepresents his policy saying that he will ship anywhere in the world. A quote "We ship anywhere in the world via USPS Priority Mail ". He refuses to ship to me directly saying he doesn't ship to Costa Rica. I have to have it sent to my US address and then forwarded, more time and money. Also he was posting a photo of the hemmed pouch but I kept receiving the unhemmed, cheaper pouches. So I switched to his supplier at a cheaper price, although since Dankung has increased their prices but it is still cheaper from me. My experiences with Dankung have always been polite, helpful, and courteous. I just move up my order point, no problem.


----------



## timdix

Some more data:
Did some testing with my preferred setup,tapered 1745 tubes about a week ago in about perfect 24C conditions.
I whipped up a board cut with long forks. By tilting the forks forward I gained another 15cm draw to my usual butterfly.
Over the chrony it was doing about 15-20fps faster than a standard butterfly with OO buck.
Consistent readings of 320-330 were obtained,max of 350.9.
This yields at least 12ftlbs with ALOT of penetrative capacity.
Take home message:roughly 1cm draw=1fps at these speeds.
I haven't been able to match these results with 1842 or 2050 tubes.

Witness the pine board taking hits at 10 metres with rounds nicely buried!


----------



## pgandy

I did some quick calculations. I couldn’t find the density of lead off hand so I used the fact there are 8 #00 buck/oz which is about 54.69 gr/ball. Using 325 fps as average that works out to be 12.8 fpe. The one shot at 350.9 fps had 14.9 fpe. I recently got serious with 1745 by using a double loop. I’ve used a single loop for some time and is my favourite for general shooting. The one double 1745 band that I’ve tested gave an average of 13.6 and 12.8 fpe during the two tests at different times. My pull length is 34”. I am still on that band set with 250 shoots testing for life before checking out variations with that tubing. I think the 1745 rubber will be the one that I’ll stick with as I can reduce my rubber inventory while obtaining good performance, and I am hoping for longer life. The double 1842 gives almost as much energy at a slightly less pull weight making it more comfortable. Since doing my PT I am pulling the double 1745 with no problem now and is becoming my favourite.


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## boby

View attachment slingshot3pdf.pdf
Recently I've reported on a physical model of a 2-section (pseudo-tapered) slingshot and its predictions. In the most recent discussion I gave results showing that velocity at constant draw (anchor) distance and pull force was better for a 2-band per side slingshot than for a 2+4 band (per side) pseudo-tapered slingshot, but worse than for a 1+2 band per side pseudo-tapered slingshot. (In my terminology, a long strand shaped into a loop with both ends connected at the pouch is considered to be 2 bands or strands.) Further analysis of this situation exposed new issues, and, I think, one approach for optimum slingshot design.

First of all, while the 1+2 band per side pseudo-tapered design seemed an improvement over the 2 band per side design, the next question was what would be the optimum length of the bands in the 2-band section of the 1+2 band design. Well, the result was that the optimum length would be zero-- which is to say a single 1 band per side (= UNtapered) slingshot is best. So, the overall drive seemed to go in the direction of minimizing the mass of the rubber bands, all the way down to one band per side. But here's the problem: the designs with 1 band per side, or 1+2, have excessive stretch factors (total length of a stretched strand divided by its unstretched length). These stretch factors at rather modest pull forces exceed what seems to be considered the maximum safe value of perhaps 5.0 or 5.5.

It turns out that one can show that the optimum slingshot design for velocity, when constrained by a maximum stretch factor, occurs at a pull force that causes the stretch factor to be the maximum allowed stretch factor. For example, if you have a 30 inch draw distance with unstretched band length of 7.5", untapered, you are operating at a Stretch Factor of 30/7.5=4.0, which is below the maximum stretch factor of (say) 5.5. A better design would use reduced unstretched band length of 30/5.5 = 5.45 inches. Such a design benefits both from allowing a larger pull force, AND lighter bands (because of their shorter length), both of which increase projectile speed.

When considering pseudo-tapered designs, calculations always show that the optimum length of the stiffer section approaches zero for highest velocity; i.e., it is best not to have the stiffer section. So optimum designs constrained by Stretch Factor will be UNtapered, and the choice of 1 or 2 or more strands of "rubber" per side will be set by how much pull force the user is comfortable with.

In the table in the attached pdf file, I show various cases illustrating these points for a 30 inch draw (from slingshot frame) shooting a 3/8 inch diameter stainless steel ball. The rows of the table highlighted in yellow give optimum designs having pull forces of 10.8, 13.8, 17.3, and 21.6 lbs, with corresponding velocities of 208, 230, 254 and 278 ft/s, all at a maximum stretch factor of 5.5. The corresponding configurations (per side) are 1 band of 2040, 1 band of 1745, 1 band of xxxx (=unknown) rubber having 1.6 times the 2040 rubber density (in g/inch), and 2 bands of 2040.

The attached pdf file also goes into my experimental determinations of the stiffness constants k1 (previously referred to as ko), and rubber density (g/inch) for 2040 and 1745 bands. I found k1=1.20 lb/inch for 2040 & 1.52 g/inch for 1745, while densities were 0.247 g/inch for 2040 and 0.317 g/inch for 1745. _A priori_, one expects the stiffness ratio of 1745 to 2040 should match the density ratio. In fact they do match: 1.27 vs 1.28. (For example 2 bands of 2040 in parallel would have twice the stiffness and twice the density if they were considered as a single effective band.). This means that one can probably skip the pull force vs draw measurements for types of bands other than 2040 and 1745, and just do mass & length measurements to get the g/inch of the other rubber types, from which you could infer the stiffness relative to 2040 or 1745. (But you need to weigh long lengths (e.g., 30 feet) to get accuracy.) If anyone has such density data for other rubbers, please share.

Using my measured force vs draw (i.e. k1 extraction) and density data for 1745 rubber, predicts a velocity of 199 ft/s for the conditions and setup that "Rayshot" used (earlier in this forum) when he measured 196-199 ft/s at "30 - 31 inch draw" (I used 30 inches in the calculation). So our physical model gives good predictions.

See the attached pdf file for more details.


----------



## Henry the Hermit

boby said:


> When considering pseudo-tapered designs, calculations always show that the optimum length of the stiffer section approaches zero for highest velocity; i.e., it is best not to have the stiffer section. So optimum designs constrained by Stretch Factor will be UNtapered, and the choice of 1 or 2 or more strands of "rubber" per side will be set by how much pull force the user is comfortable with.


I can't argue with what calculations show, but in the real world tests I made with pseudo tapered 2040, a 1:1 ratio of double to single produced higher velocities than either singles or doubles.


----------



## boby

Henry--
The concern is that your pseudo-taper worked better because you were either exceeding a maximum stretch factor on your pseudo-taper or not being at maximum stretch factor for your untapered design. To get at this, you need draw lengths, rubber type (2040 or ?), and lengths of each section of your pseudo-tapered or untapered designs, and the number of bands in each section. I totally agree that one should not be trustful of untested theory, on the other hand, theories can be a lot easier to design with than experiments once they are established. To establish a theory, one makes predictions and then everyone tries to shoot it down. Happy hunting!


----------



## pop shot

I'll sell you the tubesets and slingshots to prove your theories... I'd love to see the results match up with the theories.


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## timdix

Interesting work Boby.
I tend to agree that with pseudotapers the single strand component may well be excessively stretched beyond your "safe maximum" of 5-5.5x. I don't see this as a problem however as tubes are very robust and seem to tolerate these high stretch ratios with ease.
I just suspect your missing something in your data as your conclusions aren't borne out by the chrony. My results have shown up to a 20% increase with pseudotapers. Why this occurs I'm not entirely clear. Maybe there is a compounding effect with an acceleration component of the single strand(eg 200fps) with an additional acceleration(eg 100fps) from the double strand(highly simplistic,my apologies). 
Whatever the causative factor the pseudos have always been profoundly faster. Using them in a extended draw setup gives super fast speeds.


----------



## pgandy

As I said on the previous page theories are fine within limits. Bumble bees will testify to this, otherwise they would be grounded because theoretically they cannot. Your work would have more credibility if you published your test results, I am eager to see those results, rather than what theoretically should be happening, which is not in accordance with field findings of those reporting on such bands. As you Americans say, the proof is in the pudding.


----------



## Henry the Hermit

boby said:


> Henry--
> The concern is that your pseudo-taper worked better because you were either exceeding a maximum stretch factor on your pseudo-taper or not being at maximum stretch factor for your untapered design. To get at this, you need draw lengths, rubber type (2040 or ?), and lengths of each section of your pseudo-tapered or untapered designs, and the number of bands in each section. I totally agree that one should not be trustful of untested theory, on the other hand, theories can be a lot easier to design with than experiments once they are established. To establish a theory, one makes predictions and then everyone tries to shoot it down. Happy hunting!


OK, I think I've got it. My real world tests don't fit your theories, so I must be doing it wrong. Thank you, and please get back to me after you've done some actual chrony tests.


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## pop shot

It will be nice to see some actual tested theories for a change. We've just been wandering through this hobby with no guidance or theories to what to shoot. I use old condoms for bands because I have no idea what I'm doing.


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## LVO

I don't have a chrony, just soup cans. I do know that psuedo-taper goes POW! Double taper goes pow but harder pull. 
Singles are good fun, too. Theories make my head hurt. like POW between the ears


----------



## Henry the Hermit

pop shot said:


> It will be nice to see some actual tested theories for a change. We've just been wandering through this hobby with no guidance or theories to what to shoot. I use old condoms for bands because I have no idea what I'm doing.


Don't use the ones you find on the beach. The sand is bad for them.


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## LVO

Henry is a wise man. Navy guys have more beach knowledge than us Army guys!


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## pgandy

Henry in Panama said:


> It will be nice to see some actual tested theories for a change. We've just been wandering through this hobby with no guidance or theories to what to shoot. I use old condoms for bands because I have no idea what I'm doing.


Don't use the ones you find on the beach. The sand is bad for them.
[/quote]

I'll just take your word on it. You've been right so far.


----------



## Henry the Hermit

If you are following the Slingshot Forum 300 Club Topic, you already know that I have achieved 354 fps with pseudo tapered Dankung 1842. Here's the formula for making a set of these bands.

Overall length of each tube = 11 inches. Measure 7 inches from one end and fold that end back on the 7 inch point and tie the end to the tube. The overall length will now be 7 1/2 inches. Use the extra 1/2 inch to tie on the pouch. Here's a link to a tutorial.

file:///home/henry/web/oldpeddler/biombos/bandset-1842/index.html

I also now have a supply of 1745 tubes and will duplicate the tests made earlier on 2040 and 1842 in the near future.


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## LVO

I love that formula, Henry. You rock!


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## Tobse

yesterday we have shoot the fresh arived 20/40 and 18/42 tubes! we tapered like Henry recommend it. i have to say we are all very lucky with this tapered tubes! the efficiency is not like TB but the speed is very good! 8mm with 95 - 100 mps and 10mm with 83 - 85 mps also they are very quiet and last much longer than the bands. my favorite for smal bullets for sure.

the only problem: the loop slipped! not only mine every loop sipped! we made even two constrictor knots! was better but still sipped. we stretch the tubes to the very end maybe this is not good with tapered ??

take a look at the pics, this is how it looks after the shootout last night! it wasnt 7:6 any more








it slipped 6cm.

but all in all i am happy with this tubes.


----------



## Henry the Hermit

Tobse said:


> yesterday we have shoot the fresh arived 20/40 and 18/42 tubes! we tapered like Henry recommend it. i have to say we are all very lucky with this tapered tubes! the efficiency is not like TB but the speed is very good! 8mm with 95 - 100 mps and 10mm with 83 - 85 mps also they are very quiet and last much longer than the bands. my favorite for smal bullets for sure.
> 
> the only problem: the loop slipped! not only mine every loop sipped! we made even two constrictor knots! was better but still sipped. we stretch the tubes to the very end maybe this is not good with tapered ??
> 
> take a look at the pics, this is how it looks after the shootout last night! it wasnt 7:6 any more
> 
> 
> 
> 
> 
> 
> 
> 
> it slipped 6cm.
> 
> but all in all i am happy with this tubes.
> 
> View attachment 28466
> 
> View attachment 28467


Here is a closeup of one of my ties. Tubes are 2040, sleeve is 1745, string is waxed leather lacing twine. Use moderate stretch and tight tie. I stretch these until they bottom out and have never had one slip. Hope this helps.


----------



## pgandy

I had slippage also with thread that I got from the shoe shop. This was unwaxed thread. I solved my problem using stripes of TBG or TBS. I believe rubber bands will work.


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## Tobse

Thanks Henry, this looks realy good!

at the moment i made it like this, it slipped also not.


----------



## boby

To tie a loop for a taper I use what looks like a leather washer: a 0.75 inch diameter piece of leather (similar to pouch leather) with a 0.25 inch diameter hole punched into it. This leather washer is located at the junction of the looped and single tube sections. One end of the hole in the washer is connected to the single tube that goes to the pouch. The opposite end of the hole in the washer is connected to a folded-in-half single tube that becomes the loop when the 2 ends of the folded tube are fed together into the hole in the washer. I've been using soft cotton thread to tie






the tube ends. I find this gives rather precise control over the length of the looped section and is easy to reproduce (e.g., so that both sides of the slingshot have very nearly the same length of their looped sections). I had trouble getting this control with the method described by Tobse, which otherwise worked well and is easy. Another advantage of the leather washer method is that it allows use of different types of tubing in the single and looped sections. For example, it can be beneficial to use 1745 in the single section and 2040 in the loop section. I've attached a picture.

The method shown by Henry recently also looks attractive, but I had a devil of a time trying to get the sleeve tube in place-- maybe wider forceps or forceps with a more wedge-shaped tip would have helped.


----------



## Henry the Hermit

boby said:


> The method shown by Henry recently also looks attractive, but I had a devil of a time trying to get the sleeve tube in place-- maybe wider forceps or forceps with a more wedge-shaped tip would have helped.


I use small pointed forceps. I put the sleeve over the forceps, open them and feed both ends of a string looped over the loop I want to secure. Then I can pull the rubber through the sleeve easily. I'll try to get some pictures of the procedure tomorrow.

I have got sidetracked from the promised 1745 tests, but will try to at least do some tests on a looped 1745 set tomorrow, so we will have a base comparison with 2040 and 1842.

In the meantime, I've been trying a hybrid configuration consisting on one loop of 1745 at the fork and a loop of 2040 at the pouch, using the same 7:6 ratio. Details here - http://slingshotforum.com/topic/19795-1745x2040-tapered-tube-set-open-source-project/page__st__10#entry239068

This afternoon, I managed lots of 280+ fps, maybe a half dozen 290+ fps, and one 304 fps with this setup. I also made a similar set using 1842 and 2040. Tomorrow I'll modify another frame to test that setup. I also plan to make a bit longer set of whichever proves to be fastest to try on my Starship.


----------



## DaveSteve

Henry in Panama said:


> OK, I know that some of you guys are bored with all the discussion of lb/ft, because velocity is where the glamour is. So here are the results so far, of velocity measurements, from which the energy figures were derived. Note that with 39.7 grain .30 cal lead, pseudo-tapered outperforms looped. The looped configuration doesn't show a clear advantage until projectile weight reaches 125 grains. (.429 lead) I'm guessing that the crossover point is about 100 grains, but don't have any 100 grain ammo.
> 
> View attachment 17181


These results make me thinking about my next order tubing.


----------



## DaveSteve

M_J said:


> Looped 2040s are my favorite.
> The set I'm using now starts with a 13" length on each side so after looping and tying I get about 6.25" effective length.
> With my 31" draw these will send a 7/16" steel ammo through a free-standing Coke can at 35' so fast that it goes through and almost doesn't knock the can over. I don't have a chrony but that's fast!
> Super-smooth and easy draw as well.
> That set Jim is talking about with the heavy pull is what I shot my scored targets with at the ECST. They're fast but brutal, even at a longer length. Very unusual for 2040s.


I never thought that 2040 can be that powerful. My head is spinning now.


----------



## Henry the Hermit

This Topic is one year old today, Dec 24, 2012.


----------



## Henry the Hermit

Yesterday I finished a series of tests pitting 2040 vs 1842 vs 1745 in looped configuration. The tubes were each cut 14 inches long, resulting in a loop of slightly over 6.5 inches. Jim Harris' Performance Catapult pouches were used, and all shots were fired from my Cashew Fork Ringshooter.

A pdf of the results is attached. In the far left column is listed ball caliber and weight. Each group of 10 shots shows 5 shots velocity at an anchored draw of 32 inches, followed by 5 shots at my maximum draw. On the rows marked "Average" is the average velocity of each 5 shot group and the energy in foot pounds.

I believe that if I were a bit stronger, there would be a greater variation in velocity between 2040 and 1745, and to that end, I am going to repeat the tests with single tube per side in the near future. For now, these results tell me that with .44 lead, I can get essentially the same speed with 2040 as 1745. You younger, stronger guys can probably get more speed with 1745.

In my opinion, if you are shooting anything lighter than .50 cal steel/44 cal lead with any of these looped tube sets, you are wasting energy.

View attachment 2040-1842-1745.pdf


----------



## Dayhiker

Henry, I don't understand a f*ing thing you're saying. Just answer me this please: I am shooting 18-42 tubes at a 38-inch draw, using a very lightweight pouch. Is 45 cal. lead not a good match?

I know this is seemingly a disrespectful post. But it's really a personal question. I know Henry has the answer, but my hope is that he'll show us all how to get it in very clear terms. He's a guy who can put it that way.


----------



## Henry the Hermit

Dayhiker said:


> Henry, I don't understand a f*ing thing you're saying. Just answer me this please: I am shooting 18-42 tubes at a 38-inch draw, using a very lightweight pouch. Is 45 cal. lead not a good match?
> 
> I know this is seemingly a disrespectful post. But it's really a personal question. I know Henry has the answer, but my hope is that he'll show us all how to get it in very clear terms. He's a guy who can put it that way.


There is nothing in your post that I find disrespectful. Based on my results, and considering that you and I are probably fairly close in strength, looped 1842 with .45 lead is probably the most efficient combination for you. At that draw, you should be seeing about 210~215 fps and about 12.5 lb/ft energy with .45 lead.

As for how to find an efficient combination without a Chrony and a bunch of math and tables, here's how I would do it. Rig up OTT on a small frame with low forks, no matter what rubber you're using. If you get handslap with your chosen ammo, go heavier. If you don't, go lighter. If you are limited to one size ammo, change the band dimensions. When you find a combination that delivers good speed with very light, or no, handslap you're there. This method will not work with Ringshooters or TTF frames. Once you find the combination, you can switch to the frame you want to use.

I hope that helps.


----------



## BC-Slinger

I would like to chime in to this thread and say thanks so much for your great testing Henry. I just recently got a nice order from dankung with 1745 and 1842 tubeing and i followed your guide for tube sizes and all i have to say is wow those suckers are fast.

This is a great thread and super usefull information. :bowdown: .


----------



## shadow4848

Henry in Panama said:


> Dayhiker said:
> 
> 
> 
> Henry, I don't understand a f*ing thing you're saying. Just answer me this please: I am shooting 18-42 tubes at a 38-inch draw, using a very lightweight pouch. Is 45 cal. lead not a good match?
> 
> I know this is seemingly a disrespectful post. But it's really a personal question. I know Henry has the answer, but my hope is that he'll show us all how to get it in very clear terms. He's a guy who can put it that way.
> 
> 
> 
> There is nothing in your post that I find disrespectful. Based on my results, and considering that you and I are probably fairly close in strength, looped 1842 with .45 lead is probably the most efficient combination for you. At that draw, you should be seeing about 210~215 fps and about 12.5 lb/ft energy with .45 lead.
> 
> As for how to find an efficient combination without a Chrony and a bunch of math and tables, here's how I would do it. Rig up OTT on a small frame with low forks, no matter what rubber you're using. If you get handslap with your chosen ammo, go heavier. If you don't, go lighter. If you are limited to one size ammo, change the band dimensions. When you find a combination that delivers good speed with very light, or no, handslap you're there. This method will not work with Ringshooters or TTF frames. Once you find the combination, you can switch to the frame you want to use.
> 
> I hope that helps.
Click to expand...

Very impressive, Thanks for sharing Henry! I definitely gonna try to make a set by myself. BTW, do you know that in China, there is a new concept of bandsets? My people in China call it 'cocktail band'. It's basically a combination of 2050 and 2060. I was told that it can easily achieve 300+ FPS velocity. I am thinking maybe sometimes you can test them, and find a way to achieve higher velocity, go slingshot! 

here is the link http://www.dangongzm.com/product-140.html


----------



## Henry the Hermit

Yes, Shadow, some of our members are testing those kinds of hybrid tubes. I'll leave it to them because I shoot tubes almost exclusively in some form of loop. Thanks for the heads up.


----------



## shadow4848

Henry in Panama said:


> Yes, Shadow, some of our members are testing those kinds of hybrid tubes. I'll leave it to them because I shoot tubes almost exclusively in some form of loop. Thanks for the heads up.


Hybrid tubes! Thank you! Have they posted the result yet? Could you show me the link to the topics? I appreciate it very much! I am working on the loops now, based on your guidance. Hope it works! Thanks again!


----------



## pgandy

shadow4848 said:


> here is the link http://www.dangongzm.com/product-140.html


I have difficulty reading Chinese but the best that I can understand is the price is $50. I could not understand the quantity for that price nor shipping price. As for performance they are stating a velocity of greater than 100m/s (328fps) with 6.35mm (¼") steel ball and 90m/s (295 fps) w/8mm steel ball. It is not clear to me which of the two size T bands they were using for that. I think they compared those to 2050 which gave less than 90m/s (279fps) and 78 m/s (256 fps) respectively.

They are calling it T rubber and it comes in two sizes. The large 605020 and small 554520. The code breaks down on the large size to the large outer dia. 6.0mm and the small dia. 5.0mm with an inner hole of 2.0mm.

No one will hurt my feelings if they can correct me or come up with a more complete translation.


----------



## shadow4848

pgandy said:


> shadow4848 said:
> 
> 
> 
> here is the link http://www.dangongzm.com/product-140.html
> 
> 
> 
> I have difficulty reading Chinese but the best that I can understand is the price is $50. I could not understand the quantity for that price nor shipping price. As for performance they are stating a velocity of greater than 100m/s (328fps) with 6.35mm (¼") steel ball and 90m/s (295 fps) w/8mm steel ball. It is not clear to me which of the two size T bands they were using for that. I think they compared those to 2050 which gave less than 90m/s (279fps) and 78 m/s (256 fps) respectively.
> 
> They are calling it T rubber and it comes in two sizes. The large 605020 and small 554520. The code breaks down on the large size to the large outer dia. 6.0mm and the small dia. 5.0mm with an inner hole of 2.0mm.
> 
> No one will hurt my feelings if they can correct me or come up with a more complete translation.
Click to expand...

Man, the price is 50 CNY, about $8 for one pack which contains I think approximately 12 bands, I don't know the shipping fee, maybe I can ask them later, as I mentioned before, this kind of band basically is a combination of 2050 and 2060, The website says you can achieve 100m/s by using merely one set of this band. If you only shoot with one set of regular 2050 band, the highest velocity you can achieve will be less than 90m/s. The website also mentioned that, this kind of band can increase the velocity by 20 percent, and kinetic energy by 40%. Good Chinese man!


----------



## Henry the Hermit

shadow4848 said:


> Henry in Panama said:
> 
> 
> 
> Yes, Shadow, some of our members are testing those kinds of hybrid tubes. I'll leave it to them because I shoot tubes almost exclusively in some form of loop. Thanks for the heads up.
> 
> 
> 
> Hybrid tubes! Thank you! Have they posted the result yet? Could you show me the link to the topics? I appreciate it very much! I am working on the loops now, based on your guidance. Hope it works! Thanks again!
Click to expand...

Here is a link to one post about the hybrid tubes.

http://slingshotforum.com/topic/20352-pseudo-tapers/page-2#entry253433


----------



## pgandy

Shame on me! In my haste to get to bed, it was 0115 here I forget to look up the exchange rate. Sorry guys.


----------



## shadow4848

Henry in Panama said:


> shadow4848 said:
> 
> 
> 
> 
> 
> Henry in Panama said:
> 
> 
> 
> Yes, Shadow, some of our members are testing those kinds of hybrid tubes. I'll leave it to them because I shoot tubes almost exclusively in some form of loop. Thanks for the heads up.
> 
> 
> 
> Hybrid tubes! Thank you! Have they posted the result yet? Could you show me the link to the topics? I appreciate it very much! I am working on the loops now, based on your guidance. Hope it works! Thanks again!
> 
> Click to expand...
> 
> Here is a link to one post about the hybrid tubes.
> 
> http://slingshotforum.com/topic/20352-pseudo-tapers/page-2#entry253433
Click to expand...

Thanks very much Henry!


----------



## shadow4848

Henry in Panama said:


> shadow4848 said:
> 
> 
> 
> 
> 
> Henry in Panama said:
> 
> 
> 
> Yes, Shadow, some of our members are testing those kinds of hybrid tubes. I'll leave it to them because I shoot tubes almost exclusively in some form of loop. Thanks for the heads up.
> 
> 
> 
> Hybrid tubes! Thank you! Have they posted the result yet? Could you show me the link to the topics? I appreciate it very much! I am working on the loops now, based on your guidance. Hope it works! Thanks again!
> 
> Click to expand...
> 
> Here is a link to one post about the hybrid tubes.
> 
> http://slingshotforum.com/topic/20352-pseudo-tapers/page-2#entry253433
Click to expand...

I've read the methods they used, brilliant! but I think there are still several differences between the Pseudo Tapers and the cocktail bands. When you make a cocktail band, you don't draw the tube through another, you just combine them so that both of the tubes can achieve full-draw when you shoot, so the proportion of the two tubes is very important. If you do as the second method zwillie suggested, then the tube outside can not be full-draw I think, then you can't take advantage of the difference of bounce-back velocity between those two tubes.

here are some vids about how to make a cocktail band manually:

http://v.youku.com/v_show/id_XMzY0OTE4MTk2.html

http://v.youku.com/v_show/id_XNDE3MTE5MDEy.html


----------



## pgandy

Dankung is now offering double tapered bands. They are 38.5 cm long, 3060 in the middle and 2050 on the ends. Free shipping. Price 1.84 USD/set. I don't know how long Dankung has carried these, I just saw them today.


----------



## Henry the Hermit

I apologize for taking so long to post these results. These are the latest tests I've made with 2040, 1842, and 1745 tubes. It finally dawned on me why I consistently got less power increase than expected with 1745, and the explanation was simple. My 70 year old muscles don't allow me to pull looped 1745 as far as I can pull 2040. With that in mind, I made three sets of tubes, one from 2040, one from 1842, one from 1745. I cut them 9 inches long and looped them back at 3 inches. After attaching pouches (Performance Catapults) I had a working length of 7 inches. The loops allow near-instant band changes with my Ringshooter. I measured the maximum draw of each set at 40.5 inches +- .25 inch. Here are the results. Each shot was made at full, bottomed-out draw. Speeds are average of 5 shots. Keep in mind that less than full draw, heavier pouch, and/or lower temperature all can cause power (speed) loss. My temp was ~90 F.

2040 singles - .30 lead (40 gr) = 271 fps : .44 lead (118 gr) = 189 fps : .50 lead (175 gr) = 167 fps

1842 singles - .30 lead (40 gr) = 275 fps : .44 lead (118 gr) = 202 fps : .50 lead (175 gr) = 170 fps

1745 singles - .30 lead (40 gr) = 294 fps : .44 lead (118 gr) = 221 fps : .50 lead (175 gr) = 191 fps

So, I discovered a couple of things. 1745 is, at any practical ammo weight, faster (more powerful) than 1842 or 2040. Looped 1745 is a bit stiff for Geezers like me if you want to pull it to maximum draw. Younger, stronger shooters will find an advantage in 1745. The differences in 2040 and 1842 is largely in pull weight.

For my next tests, I'm going to try to up my Speed Freak standings with pseudo tapered 1745.


----------



## Wingshooter

Excellent Henry, One thing that i would add about the 1745 tubes is that they last a little longer in my setups anyway. I too have trouble with the doubles so I shoot singles or tapered. Thanks for posting this.

Roger


----------



## JetBlack

Henry your draw is around 36-38 inches right? So the length of tubing for that is nine inches? How much length do you use up on the 
Pouches,One inch or so? Let me know please


----------



## Henry the Hermit

JetBlack said:


> Henry your draw is around 36-38 inches right? So the length of tubing for that is nine inches? How much length do you use up on the
> Pouches,One inch or so? Let me know please


For these tests, I drew the tubes until they bottomed out, a bit more than 40 inches. The pouch tie uses about 1/2 inch. The working length on these tubes was just under 7 inches, giving a stretch factor close to 6:1. With looped tubes, a good working formula is draw/5.5 x 2 + pouch tie. Here's an example:

((33 inch draw / 5.5) x 2) + (1/2 inch pouch tie x 2)

or

12 + 1 = 13 inches cut length.


----------



## JetBlack

Sounds like 8 inches overall, thanks


----------



## pgandy

I gave the tube bands a go after experiencing what I considered too short of a life with flat bands. In the low power range life was OK but in the ranges I like I estimated 250 shots was giving excellent service with 200 being more realistic. As everything needs to be imported I was less than satisfied. So I gave a full loop, factory style, of 1842 a go. I found that most breaks were at the pouch and was able to retie one time but by cutting the band 1" longer I was able to get an extra retie with no noticeable difference in performance to the eye. All of this was before keeping records and estimated a total of about 1000 shots with a band set when counting the 2 reties. When Henry came along with his pseudo tapers and I went that route as I got more power with less draw force but the band life went down, but still better than I got with the flats. Most all breaks were at the tie with the loop. I have started using a cuff there and that seems to help, but need more testing. Just started with cocktail bands and they appear to have better life than the pseudo bands without cuffs (no tie at a loop) and are giving more power than a single pseudo band up to and including 2050. So far they look promising, but need much more testing in this area. However, looking over the records 1745 seemed to give the best service so I went back to the full loop using 1745 as a test for general shooting sessions. I am getting about 10 fpe which is more than sufficient for plinking at targets and should take small game, but I would opt for more power for that. Shortening the bands will bring this up. So far I've gotten 1465 shots with that band set with no breaks. At the 1400 shot point it was down about 1 fpe across the board with all types of projectiles. The bands still function but the accuracy seems to be down somewhat so for now I have retired that set and am using its sister replacement and the accuracy has picked back up. I'll go back to that set later to ensure that I just wasn't in a slump. That set has given me nearly 1500 shots and is still going? Still going or not, I am impressed. The proof will come to see what service its sister band which only has 100 shots on it will deliver.

I have a 34" draw and cut the tubes 17¼" long before tying.


----------



## pgandy

I wasn't sure to start a new thread but judging from the title this post is appropriate here. I finally received the double tapered 2050/3060 tubes from Dankung. These are tubes that measure 3060 in the middle and the ends taper down to 2050. The concept intrigued me and this is what I found:

Dankung lists them as 38.5 cm in length. After tying I got a loop measuring 7 1/8" from the pouch's edge.

I had trouble mounting the bands. I had just received a new ss a couple of days before that was still unused and that is what I intended to use. However, the cuts for inserting bands were too narrow, or the band too thick depending on one's view. I had another ss that I knew had wider cuts so I swapped. The pull was about 29#. I can pull it but I worry about what that may do to me in the long run so I was glad when the 60 shot break in and testing begin. The first 10 were shot as a series and I was impressed with the authority the set packed. After that I did 5 shot groups extended over time to save my joints during the next 50 shots. I became more and more disenchanted with the set. The first impression was misleading. The first flag that went up was using those 1 gm clay balls. The first ball stopped inside an aluminium can and the second dented it. As I had another ss in the other pocket with a double pseudo taper 1745 rubber still not broken in and let one go and got complete penetration as expected. When the 60 shot break in was over I clocked .50 cal lead. With 4# greater pull I was getting less energy than with double pseudo taper bands.

Further info 2050/3060 vs 1745 pseudo taper bands doubled:

Price (rubber only no shipping, customs, etc.)

$1.84 vs $1.03. I suspect longer life with 2050/3060, so the difference could be misleading.

Across the board I get 1-3 more fpe with double pseudo tapered 1745 depending on the configuration.

4-6# less pull with double pseudo taper 1745 again depending on the configuration.

For me, other than possible longer life, Henry's double pseudo tapered 1745 has it over the 2050/3060.

As I do not intend to use the 2050/3060 bands as is and have 4 unused pairs I think that I'll try them with a pseudo taper as my next project.


----------



## Henry the Hermit

I don't think you will see the benefit of these tubes until you shoot some really heavy ammo. Thicker tubes are always going to be slower than thinner if they are not fully loaded. You will reach a point where the thicker rubes will be faster than the thinner, but I'm guessing it will be somewhere around 300 grains.


----------



## pgandy

Henry in Panama said:


> ...I'm guessing it will be somewhere around 300 grains.


Noted.


----------



## stej

Henry, will you test also other tubes? The thicker ones like 2050, 3050, 3060,... ?


----------



## Henry the Hermit

stej said:


> Henry, will you test also other tubes? The thicker ones like 2050, 3050, 3060,... ?


No, stej, I'll leave that for the younger guys. 1745s are about the heaviest I care to pull.


----------



## jokso

Today I decided to play...took old looped tubes that came with this slingshot(think its 1745) and moded them to pseudo taper.







The bands you see attached I use every day -







For fork loop I used double folded 3mm pieces(rings) that were originally pouch ties on this looped tubes, and for pouch 3mm rings I cut from my old marksman tube, and they hold really good. When I wanted to try shooting with longer or shorter loop, or adjust my draw length on pouch just put some spit and adjust, few minutes later its ready and no slipping.








Results? Pretty much disappointed....no mather what ratio of single to loop I tried, it is too easy to pull, it just doesn't have enough force to propell 3/8 steel or 8.5mm lead to useful speed. Tri-band I normally use is much more faster, although it requires 5x pulling force for just 2x more speed, it is still 2x more speed, and I bench press 250 pounds so I can manage that...

Double pseudo 1745 should performe much better but dont have more tubes to try. I did order 15 feet of 1842, I'll give it a try it arrives


----------



## Knotty

jokso said:


> ... Tri-band I normally use is much more faster, although it requires 5x pulling force for just 2x more speed, it is still 2x more speed, and I bench press 250 pounds so I can manage that... Double pseudo 1745 should performe much better but dont have more tubes to try. I did order 15 feet of 1842, I'll give it a try it arrives


Makes sense. When speed is doubled the energy increases by the square, so you're talking about four times as much energy. That's why you had to pull so much harder.

Of course pulling harder doesn't always guarantee the speed increase expected because of the way elastics operate.


----------



## Henry the Hermit

I'm not sure what you consider useful speed, but I shot 280 fps with pseudo taper 1842 and 3/8 steel. What speed are you getting with the triple tubes?


----------



## jokso

Somewhere around 200 fps, measured in audacity, didn't measure pseudo but it was waay slower....I know I'm doing something wrong but what?I also got fingers slapped each time with pseudo


Knotty said:


> Of course pulling harder doesn't always guarantee the speed increase expected because of the way elastics operate.


I learned that hard way, when I got therabend silver tubes...it must meant to be welded by a terminator, it was heavy like a scuba spear gun bands. And when I shot it speed was slower than normal tubes


----------



## Henry the Hermit

jokso said:


> Somewhere around 200 fps, measured in audacity, didn't measure pseudo but it was waay slower....I know I'm doing something wrong but what? I also got fingers slapped each time with pseudo


Audacity can be tricky to interpret, but if you are getting consistent readings, you are probably doing it right. You should be getting over 200 fps with the 3-tube slingshot and .50 cal lead. That setup screams for heavy ammo.

Just looking at your rigs, I believe a big part of your problem is the thick, heavy pouch. The handslap with pseudo comes mostly from the heavy pouch. There are several Vendors here who can fix you up with strong, lightweight pouches.

Just don't quit. I'd like to see your name in the SSF 300 Club.


----------



## jokso

Thats the pouch i salvaged from marksman tubes
If any vendor has reasonable shipping costs to Europe I'll try light pouches.

Dont have access to heavy ammo, 3/8 steel and 8.5mm(00 buckshot) lead is my choice so I have to build on that. And 250-280 fps with it is very useful.

What about this pouch - 
Non magnetic-  Performance size;   68mm long (2 11/16 in.)
5/8 with 5.0 mm (3/16) center hole?


----------



## Henry the Hermit

jokso said:


> Thats the pouch i salvaged from marksman tubes If any vendor has reasonable shipping costs to Europe I'll try light pouches. Dont have access to heavy ammo, 3/8 steel and 8.5mm(00 buckshot) lead is my choice so I have to build on that. And 250-280 fps with it is very useful. What about this pouch - Non magnetic- Performance size; 68mm long (2 11/16 in.) 5/8 with 5.0 mm (3/16) center hole?


That pouch should work fine if it's not too thick. Most of the pouches I use weigh 1.5 grams or less. For speed shooting, I use home-made pouches that weigh about .5 gram. For power shooting, I use my home-made pouches made from fairly thick leather. They measure 3x1 inches and weigh about 3.0 grams.

Look through our Vendors and send them PMs telling them what you want. Most of them will ship to Europe.


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## jokso

Ok thanks


----------



## jokso

1842 is here!
First tried single pseudo, visually was slow so I didn't bother to measure speed. Then, double looped, visually very very fast but too hard too pull, aiming is very hard so again didn't measure it.
Finally double pseudo, pull was just right, not to hard not too low....readings were consistent 228-230fps, with 8.5mm lead








You can see the piece of tube used for tying, on the fork side 2 x triple folded, pouch side 1 x triple folded


----------



## pgandy

What overall length is your band, what ratio did you use, and finally what is your draw length? If you don't mind me asking.


----------



## Northerner

I have single 1842s on my little Bat frame. The tubes measure 5.5" from fork to pouch. Pouch is 2 3/4" long. Draw length 32". Velocity is 203 fps with 3/8" steel (9.5mm).

Cheers,

Northerner


----------



## jokso

[ quote name="pgandy" post="270213" timestamp="1364226098"]
What overall length is your band, what ratio did you use, and finally what is your draw length? If you don't mind me asking.[/quote]
Around 14.17 inches overall, ratio you can see on the pic, don't know my draw lenght, once I set the tubes, i just adjusted ratio to match my draw


----------



## stej

I see Dankung added more tubes. One of them is 3050 which should be weaker than 1745. Anybody who has Chrony and would like to compare 3050 to others?

Cross section area

1745: 13.6mm^2

3050: 12.6mm^2


----------



## halbart

Henry in Panama said:


> 'pop shot' said:
> 
> 
> 
> It will be nice to see some actual tested theories for a change. We've just been wandering through this hobby with no guidance or theories to what to shoot. I use old condoms for bands because I have no idea what I'm doing.
> 
> 
> 
> Don't use the ones you find on the beach. The sand is bad for them.
Click to expand...

I think they're pretty good. they've got some grit.


----------



## pgandy

My newest configuration is 1745 tubing cut to 17¼". It pitches a .38 cal. lead ball w/34" draw 182 fps, but the clincher is the life. I retired the first set after 1467 shots. It was still working but power was down about 1 fpe. I am on the second set with over 1500 shots and see no real noticeable power lose. I still use double bands pseudo tapered and a cocktail, but for general shooting that single loop of 1745 working great for me and my pocket book is thanking me.


----------



## Stonepark

I think you will find 3050 has a cross section of 16mm2.I use 3050 on my sniper (3 bands per side, 17 cm length for 30 inch draw) and it is definitely stronger.


----------



## hoggif

My spreadsheet as well gives 12.6mm² for 3050.


----------



## Dr J

Thanks for sharing all this useful information. Very much appreciated.


----------



## boby

pgandy said:


> My newest configuration is 1745 tubing cut to 17¼". It pitches a .38 cal. lead ball w/34" draw 182 fps, but the clincher is the life. I retired the first set after 1467 shots. It was still working but power was down about 1 fpe. I am on the second set with over 1500 shots and see no real noticeable power lose. I still use double bands pseudo tapered and a cocktail, but for general shooting that single loop of 1745 working great for me and my pocket book is thanking me.


Those are great lifetimes. Can you describe your pseudo-taper tie and, if relevant, your fork tie that lets you get so many shots? (What is a "cocktail"?). Also, can you tell me the lengths of the single and doubled sections of your pseudo-taper that had 182 fps. Also, when you say "single loop" of 1745, do you mean a single strand (e.g., tied at fork and pouch), or a single strand folded back and tied only at the pouch, which really acts like two strands? Thanks.


----------



## pgandy

I think you misread that post and I'll try to address each of your questions with all references using 34" draw and in the first two cases 1745 rubber only.

First the single loop (aka factory style) that is giving me such good life, 1540 shots as of this morning, is one length of rubber cut to 17¼" with both ends tied to the pouch. I just measured the set in use and it is 8" from pouch to fork. There is no fork tie as I use Dankung type catty, I just snap in place making changing a band set a snap, literally. It is that set that I clocked 182 fps w/.38 lead.

Second, the pseudo taper. I pretty much followed Henry's lead using his initial ratio 4:3. That is the loop was 4" long with the pouch an additional 3" away. When he changed to a 1:1 ratio I followed suit. However for me I found the 4:3 gave more power and have gone back to that. And now make them slightly longer although in theory the shorter length would be faster. I now mark the tube at 8.375" and fold the end back to that mark and tie. I increased the single section form first tie to pouch to 3.125". I now use the pseudo tapered bands only in doubles, that is two bands per side. I get an average of averages of 207 fps w/.38 lead. I prefer .50 lead at 181 fps. But by far shoot more 6.8 g hex nuts at 205 fps.

Third, a cocktail is a band set using two different size tubes, one end nested inside the other's end. I use 2050/1745. This gives more power than a single loop but not as long life. And more power and life than a single pseudo band but not as much power as a double set. Perhaps this link will help. http://slingshotforu...e-2#entry253433 Scroll about halfway down to Zwillie. I've been using one loop of 2050 with 1745 inserted in both ends and tied to pouch like in the second method. I am not saying my 2050/1745 is the best. It was all I had to work with and I like it. No doubt there are a better combinations.

http://v.youku.com/v_show/id_XMzY0OTE4MTk2.html


----------



## pgandy

Sorry, for the cocktail I use 2050/1842 AND NOT 2050/1745. The reason being I had a hard time inserting the larger 1745 into the 2050. I think the 2050/1745 would give better performance and better life. Maybe one day I'll be able to make the 1745 work, I hope.


----------



## drnoob

Can you guys help me out? I have a flippinout scout and I want to try loops. I have a 32 inch draw and I only shoot 3/8 steel. I want to be around 230 fps to 250 fps (around). Can you experienced guys tell me something I could buy that could achieve this? Longer lasting would be great also


----------



## muddog15

Unless I missed the answer to this question I'm looking for a good tube size to shoot with 1/2 . 50 cal steel and 7/16 . 44 cal lead. The few ive tried didn't work for me very well. The True Mark tubes seem to work the best.


----------



## JetBlack

1842 or 2040s would be great looped for that ammo and will Last.Jim on the forum sells band sets if you're not ready to make them yet. so does wingshooter I believe


----------



## JetBlack

Muddog, single 1745s work well from my experience with 716 steel, half inchor 44 caliber lead, I suggest single 2050 s or looped 1745s,, they will also shoot 716 steel with a little leftover energy but not enough for a band slap


----------



## wangyue

我们中国的玩家都在玩内穿鸡尾酒皮筋 比如2050内穿2040 大管内穿小管http://v.youku.com/v_show/id_XNDU3MzMzMDY0.html可以看这个链接


----------



## pgandy

wangyue said:


> 我们中国的玩家都在玩内穿鸡尾酒皮筋 比如2050内穿2040 大管内穿小管http://v.youku.com/v_show/id_XNDU3MzMzMDY0.html可以看这个链接


I like cocktails and have been using 2050/1842. I will try 2050/2040. Thanks.


----------



## wangyue

不同的配置都有人试过有些玩家不喜欢内穿觉得会影响皮筋寿命 就做前面4股后面2股这样寿命更长可以打1000发钢珠


----------



## pgandy

wangyue said:


> 不同的配置都有人试过有些玩家不喜欢内穿觉得会影响皮筋寿命 就做前面4股后面2股这样寿命更长可以打1000发钢珠


I have only tried 2050/1842 and 2050/1745. I had trouble making with 2050/1745 so did not use it. I have only used 2050/1842 but will make a band of 2050/2040 soon. I think the 2050/1842 will give longer life. Sorry my Chinese is not good and think that is what you are asking.


----------



## ruthiexxxx

I have a question. I've been very good and looked through the thread from the beginning! Lots of wonderful info about Chinese tubes...to which I am new....but no mention of Dankung's 50/80s. I got some of this from a lovely guy in the USA and (subjectively speaking) the performance is brilliant. I have it in a short double (only enough to do one SS) and my impression is that it outperforms TTB. I wondered if anyone had done such a comparison test...or just what y'all think of it.


----------



## pgandy

pgandy said:


> wangyue said:
> 
> 
> 
> 我们中国的玩家都在玩内穿鸡尾酒皮筋 比如2050内穿2040 大管内穿小管http://v.youku.com/v_show/id_XNDU3MzMzMDY0.html可以看这个链接
> 
> 
> 
> I like cocktails and have been using 2050/1842. I will try 2050/2040. Thanks.
Click to expand...

I compared the cocktail 2050/2040 to cocktails that I had been using 2050/1842 and 2050/1745. In the case of the 2050/2040 and 2050/1745 the data reflects only one band set, something that I don't like doing. In the case of the 2050/1842 several bands sets and configurations were used as this is the set that I have settled on, so more data is available. In the case of the 2050/1754, I've shied away from this because of the difficulty of me inserting the 1745 tube. I am getting better at the construction now and will have another go at those in the future.

The 2040 tube appears to work better with the lighter projectiles, something I think the Chinese favour. I used the 2050/2040 set as the basis in which to compare the other two.

With a 1 g clay ball: the 1842 was about equal and the 1745 gave about 20% less fpe.

With a .38 lead ball: the 1842 gave about 7% more fpe while the 1745 was about equal.

With a .50 lead ball: the 1842 gave about 9% and the 1745 gave about 12% more fpe.

It's too soon tell about life but historically I've gotten more out of 1745. I will continue to use the 1842 while taking another look at the 1745 as my building skill has improved.


----------



## wangyue

It came to mean do not quite understand, but we wear cocktail in a special tool, do wear in a very convenient. The only way of practical to find suitable configuration, for example, some people like to play in the 8 unit 2040 and doesn't like to play wearing the same.

虽然翻译过来意思不大明白 但是我们内穿鸡尾酒都有专门的工具，做内穿非常方便。只有不停的实用才能找到适合自己的配置，比如有人喜欢玩8股2040却不喜欢玩内穿一样。


----------



## wangyue

不同的狩猎方式及环境对胶管性能要求不同，我有个朋友他是用1632/1632配8mm钢珠他觉得这个就很好。可有些人却要用不同的配置我自己用的是2053/204觉得这个适合自己。 因该要因而人而议不过有专用的鸡尾酒工具可以更快的做鸡尾酒
Different forms of hunting and the environment on properties of Rubber Hose requirements are different, I had a friend who is one thousand six hundred and thirty two-one thousand six hundred and thirty seconds with 8mm steel ball he thought it would be nice.Some people want to use different configuration I used two thousand fifty three-two hundred and fourths thought this for myself. As a result of the to which people on the faster - but is there a special cocktail tool can do a cocktail


----------



## JetBlack

wangyue said:


> 不同的狩猎方式及环境对胶管性能要求不同，我有个朋友他是用1632/1632配8mm钢珠他觉得这个就很好。可有些人却要用不同的配置我自己用的是2053/204觉得这个适合自己。 因该要因而人而议不过有专用的鸡尾酒工具可以更快的做鸡尾酒
> Different forms of hunting and the environment on properties of Rubber Hose requirements are different, I had a friend who is one thousand six hundred and thirty two-one thousand six hundred and thirty seconds with 8mm steel ball he thought it would be nice.Some people want to use different configuration I used two thousand fifty three-two hundred and fourths thought this for myself. As a result of the to which people on the faster - but is there a special cocktail tool can do a cocktail


what is this cocktail tool?Id buy one in a second if it makes tapers eaisier...


----------



## Shot3883

Hi,

New to the forum and have been reading these posts but still not sure of the purpose of these tests with the pseudo tapered setup. I assume it is to reduce the power for smaller shot rather than having a complete loop which produces to much energy causing hand slap problems. Why not just use looped 2040s to reduce the power instead of pseudo tapered 1745s

?


----------



## Henry the Hermit

Shot3883 said:


> Hi,
> 
> New to the forum and have been reading these posts but still not sure of the purpose of these tests with the pseudo tapered setup. I assume it is to reduce the power for smaller shot rather than having a complete loop which produces to much energy causing hand slap problems. Why not just use looped 2040s to reduce the power instead of pseudo tapered 1745s
> 
> ?


The purpose was to gain velocity with lighter ammo, and the pseudo taper works very well for that use.


----------



## Shot3883

Henry in Panama said:


> Shot3883 said:
> 
> 
> 
> Hi,
> 
> New to the forum and have been reading these posts but still not sure of the purpose of these tests with the pseudo tapered setup. I assume it is to reduce the power for smaller shot rather than having a complete loop which produces to much energy causing hand slap problems. Why not just use looped 2040s to reduce the power instead of pseudo tapered 1745s
> 
> ?
> 
> 
> 
> The purpose was to gain velocity with lighter ammo, and the pseudo taper works very well for that use.
Click to expand...

So am I right in thinking that if you use the band as a complete loop instead of the pseudo tapered set-up then the velocity of the projectile is reduced? If this being the case where has all the extra energy gone?


----------



## JetBlack

I think they are more efficient than being fully looped and have that tapered effect.maybe someone with better understanding will reply..


----------



## hoggif

I think pseudo-tapers differ from full loops in two ways: The weight of a single tube at the pouch end is less than two tubes as in full loop. Therefore you accelerate one or two tube ends with the ammo. Less tube to accelerate means more energy into the ball and pouch (if you get the same amount of energy into the total acceleration). The difference can be neglible with very heavy loads but with light loads it becomes more signifficant. This is similar to why lighter pouches are preferred for faster speed with light ammo.

The other difference is pulling it to the max. With one tube attached to two tubes (pseudotaper) you will max out the single tube section more easily. Pulling full loop to max requires more force.


----------



## Shot3883

Thanks Hoggif,

I guessed it was a way for the tubes to emulate the Theraband flats tapered. Thanks for the clear explanation.


----------



## pgandy

If you put a couple of reference marks on the double band section and do the same on the single band section you will see that the single section stretches more. Am not sure what lighter balls refers to but up through and slightly pass .50 cal lead I get more velocity with pseudo taper. I don't know how much higher I can go. I get longer life with full loops usually throwing them away after 1600 shots because they are tiring, not breaking.


----------



## Tube_Shooter

Remember whatever band/tube set up its best to get them warm before use especially in cold climates like the UK,latex like myself hates the snow.We had recently some milder weather 34 C(unusual for UK) and I noticed a fair increase in velocity,I need a mini sun for my pocket


----------



## Henry the Hermit

Shot3883 said:


> So am I right in thinking that if you use the band as a complete loop instead of the pseudo tapered set-up then the velocity of the projectile is reduced? If this being the case where has all the extra energy gone?


That is partly correct. In all my tests, a full loop of the same type of rubber had less velocity, up to a point, than pseudo taper. One reason is that full loops are heavier than pseudo taper, and the full weight of what the rubber has to accelerate includes 1/2 of the rubber itself, the pouch and tie, and the ammo. Another reason is that the single section will be stretched to a greater extent than the looped sections. In many cases the single section will be bottomed out. This causes it to contract faster, and because the ratio of ammo weight to pouch/tie/rubber is greater, more energy will be transferred to the ammo. There is no extra net energy in a full loop over a pseudo taper unless the full loop can accelerate faster than the pseudo taper. Hope this helps.


----------



## Shot3883

Henry in Panama said:


> Shot3883 said:
> 
> 
> 
> So am I right in thinking that if you use the band as a complete loop instead of the pseudo tapered set-up then the velocity of the projectile is reduced? If this being the case where has all the extra energy gone?
> 
> 
> 
> That is partly correct. In all my tests, a full loop of the same type of rubber had less velocity, up to a point, than pseudo taper. One reason is that full loops are heavier than pseudo taper, and the full weight of what the rubber has to accelerate includes 1/2 of the rubber itself, the pouch and tie, and the ammo. Another reason is that the single section will be stretched to a greater extent than the looped sections. In many cases the single section will be bottomed out. This causes it to contract faster, and because the ratio of ammo weight to pouch/tie/rubber is greater, more energy will be transferred to the ammo. There is no extra net energy in a full loop over a pseudo taper unless the full loop can accelerate faster than the pseudo taper. Hope this helps.
Click to expand...

Thanks, I understand much better now. 

I read somewhere that 8-strand 2040 (two loops per side) is the bomb!

Roughly, what kind of fps could I expect to see if I use 8-strand 2040 (two loops per side) in a pseudo taper 4:3 setup using 12mm lead and a pull of 44inch. Bands cut to 16inch and looped at the 6 inch mark, which I am guessing is about 4:3 ratio.


----------



## ruthiexxxx

2 loops a side of 20/40 is good...3 loops a side is quite powerful


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## JetBlack

Slightly ot but really liking 2050 singles with half inch steel.thanks wing shooter! Oh yeah pulled to 50 inches...


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## pgandy

For me 2040 pseudos worked better with lighter ammo. 1745 with .50 cal. lead gave me better velocity and better life.


----------



## Henry the Hermit

Shot3883 said:


> Henry in Panama said:
> 
> 
> 
> 
> 
> Shot3883 said:
> 
> 
> 
> So am I right in thinking that if you use the band as a complete loop instead of the pseudo tapered set-up then the velocity of the projectile is reduced? If this being the case where has all the extra energy gone?
> 
> 
> 
> That is partly correct. In all my tests, a full loop of the same type of rubber had less velocity, up to a point, than pseudo taper. One reason is that full loops are heavier than pseudo taper, and the full weight of what the rubber has to accelerate includes 1/2 of the rubber itself, the pouch and tie, and the ammo. Another reason is that the single section will be stretched to a greater extent than the looped sections. In many cases the single section will be bottomed out. This causes it to contract faster, and because the ratio of ammo weight to pouch/tie/rubber is greater, more energy will be transferred to the ammo. There is no extra net energy in a full loop over a pseudo taper unless the full loop can accelerate faster than the pseudo taper. Hope this helps.
> 
> Click to expand...
> 
> Thanks, I understand much better now.
> 
> I read somewhere that 8-strand 2040 (two loops per side) is the bomb!
> 
> Roughly, what kind of fps could I expect to see if I use 8-strand 2040 (two loops per side) in a pseudo taper 4:3 setup using 12mm lead and a pull of 44inch. Bands cut to 16inch and looped at the 6 inch mark, which I am guessing is about 4:3 ratio.
Click to expand...

Any answer I gave to that question would be a guess. My 70+ year old arms complain too loudly when I try to pull anything over about 20 pounds, so I haven't done much testing with heavy pull bands. However, in looking over my tests, the fastest speed I ever recorded with looped 2040 was 276 fps with .30 cal lead (40 grains), so as a guess, I'd say you should be able to get 240~250 fps with .50 lead, maybe a bit more if you can bottom the tubes out.


----------



## Shot3883

Henry in Panama said:


> Shot3883 said:
> 
> 
> 
> 
> 
> Henry in Panama said:
> 
> 
> 
> 
> 
> Shot3883 said:
> 
> 
> 
> So am I right in thinking that if you use the band as a complete loop instead of the pseudo tapered set-up then the velocity of the projectile is reduced? If this being the case where has all the extra energy gone?
> 
> 
> 
> That is partly correct. In all my tests, a full loop of the same type of rubber had less velocity, up to a point, than pseudo taper. One reason is that full loops are heavier than pseudo taper, and the full weight of what the rubber has to accelerate includes 1/2 of the rubber itself, the pouch and tie, and the ammo. Another reason is that the single section will be stretched to a greater extent than the looped sections. In many cases the single section will be bottomed out. This causes it to contract faster, and because the ratio of ammo weight to pouch/tie/rubber is greater, more energy will be transferred to the ammo. There is no extra net energy in a full loop over a pseudo taper unless the full loop can accelerate faster than the pseudo taper. Hope this helps.
> 
> Click to expand...
> 
> Thanks, I understand much better now.
> 
> I read somewhere that 8-strand 2040 (two loops per side) is the bomb!
> 
> Roughly, what kind of fps could I expect to see if I use 8-strand 2040 (two loops per side) in a pseudo taper 4:3 setup using 12mm lead and a pull of 44inch. Bands cut to 16inch and looped at the 6 inch mark, which I am guessing is about 4:3 ratio.
> 
> Click to expand...
> 
> Any answer I gave to that question would be a guess. My 70+ year old arms complain too loudly when I try to pull anything over about 20 pounds, so I haven't done much testing with heavy pull bands. However, in looking over my tests, the fastest speed I ever recorded with looped 2040 was 276 fps with .30 cal lead (40 grains), so as a guess, I'd say you should be able to get 240~250 fps with .50 lead, maybe a bit more if you can bottom the tubes out.
Click to expand...

Would that be with pseudo taper?


----------



## JetBlack

Henry always shoots some sort of loop so I'm guessing, yes.


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## Shot3883

What kind of percentage increase in fps does pseudo give over regular loops. Is it on par with flat bands regular vs tapered which in a test was about 16% more fps on average.


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## zwillie

Hi,

I shoot tapered tubes.










Sometimes I recycle old short pieces of tubes and loop them in this way.





































Cheers

Zwillie


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## JetBlack

I have a similar idea for scraps.experimenting tomorrow so I'll post findings


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## Mr.Teh

Nice idea for recycling old bandsets !


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## Shot3883

zwillie,

How do you get the two ends of the tube into the single tube when you recycle your old short pieces? I have lots of spare pieces as the tubes tend to get damaged in the vice when I stretch them to rap the thermaband round, so would like to try what you have done.


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## JetBlack

Hemostats, that's how I do it.look at my frankentaper thread, another way to salvage tubes.need to know how to make tapers for either method though.


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## zwillie

Shot3883 said:


> zwillie,
> 
> How do you get the two ends of the tube into the single tube when you recycle your old short pieces? I have lots of spare pieces as the tubes tend to get damaged in the vice when I stretch them to rap the thermaband round, so would like to try what you have done.


Hi,

I open the end of the single tubes about 2" with the ring pliers showen in the pic and stuck both ends of the loop in it.

Zwillie


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## Shot3883

Thanks, I will check out the frankentaper thread and buy some ring pliers.


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## Shot3883

Are there any guides on the best way to make the pseudo taper. I am new to this and keep finding after stretching the tubing and applying the rap and tuck with the thermaband that the slingshot bands are of unequal lengths.

Also I am getting a lot of damaged tubes trying to make the pseudo tapers. I am holding the joint in place with a Hemostat but I first wrap a piece of leather around the joint. After stretching the tubes for the thermaband rap and tuck method the tubes show signs of damage.


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## JetBlack

I like wing shooters way, he has a video on his site or YouTube.


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## Tube_Shooter

I'm glad this topic is pinned it's a great source for information when it comes to tubes,for instance I thought I'd take a gander and found people using scraps into tapered sets before I binned all scrap tubes not anymore,cheers <_<


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## pgandy

I became curious as to which of my band sets affected accuracy the most, if at all. I used three band sets, a full loop (factory style) of 1745, my practice band as I get 1600 shots before retiring, my most economical band set. A 2050/1842 cocktail, my favourite shooting band and a double 1745 pseudo taper, my most powerful. I recorded the hits and misses on all types of targets shot under all conditions at various ranges over a period of several months. This is what I came up with:

The 1745 full loop scored 65% & 59% depending on slingshot

The cocktail 73%

The double 1745 pseudo taper 63%


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## zwillie

Hi,

here one of my tapered tube sets.

TTR through TTG (not easy to do) and just for heavy ammo.





































Zwillie


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## ruthiexxxx

OMG Zwillie...that cannot have been easy to do !!

I'd love to hear more about this. Technique of insertion and performance.

I've only tried two types of cocktail tubes (full length). One was Green DubDub with a natural latex inner...which is still going strong and another with 50/80s with 20/40s inside. These were great but unfortunately the 50/80 snapped after not very many shots so I haven't bothered again


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## zwillie

Hi Ruthie,

here the way I make the tapered tubes

http://slingshotforum.com/topic/21125-real-tapered-tubes/

Zwillie


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## ruthiexxxx

zwillie said:


> Hi Ruthie,
> 
> here the way I make the tapered tubes
> 
> http://slingshotforum.com/topic/21125-real-tapered-tubes/
> 
> Zwillie
> 
> thanks amigo...very interesting !!


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## JJSyd

I don't have much to contribute but I would like to say thanks.

I read the whole thread word for word in 1 sitting lol


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## pgandy

WOW! That was some undertaking for one setting.


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## kwinpr

So much great info in this thread. Thanks to everyone for sharing!


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## Kerry Cornelius

Henry in Panama said:


> "So, what a coincidence that our band measurements are so close."
> 
> Great minds think alike!
> 
> "What would be the best way to tie off the short loop?"
> 
> I use black waxed string that I buy from my local leather shop. It's roughly the same diameter as the cotton kite string I used to buy, but much stronger.
> 
> Now for the good news.
> 
> *I did it!!!*
> 
> 
> 
> 
> 
> 
> 
> 
> chrony-300-01.jpg
> 
> And here are the bands I used. Length of one side 6.5 inches. The loop is just long enough to fit well on the Dankung. BTW, with the amount of shooting I'm doing, the Dankung is just too uncomfortable, so all future tests will be with Mr. Stubby. I've found no difference in performance but a huge difference in comfort.
> 
> 
> 
> 
> 
> 
> 
> 
> looped-single-300fps.jpg
> 
> Now for some BBs.


What size tubes are you using. I would like to use your design. (Copying is the highest form of complimenting!!! LOL)


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## Carbon

I use a partial butterfly draw when shooting that comes out to 62in or 157cm. I also shoot 3/8" steel (and 5/8" marbles that weigh close to the same) and I'm looking for the right setup.

I've been using 1745 tubes but they are a little too slow for my liking. I want a FAST setup, something that will turn that 3/8" steel into a penetrating projectile. But I'm a little lost because it looks like Henry's tests were done with a draw that is almost half the length of mine. Should I just scale it up?


----------



## boby

Carbon said:


> I use a partial butterfly draw when shooting that comes out to 62in or 157cm. I also shoot 3/8" steel (and 5/8" marbles that weigh close to the same) and I'm looking for the right setup.
> 
> I've been using 1745 tubes but they are a little too slow for my liking. I want a FAST setup, something that will turn that 3/8" steel into a penetrating projectile. But I'm a little lost because it looks like Henry's tests were done with a draw that is almost half the length of mine. Should I just scale it up?


You should get Henry's take on this, but to me "scaling it up" would be to use the same stretch factor (ratio of stretched total length to unstretched total length, with same ratio of 1-tube to 2-tube section unstretched lengths). This will give you the same draw force as Henry, but the increased draw length from butterfly will increase the projectile energy by about the ratio of draw lengths, and the projectile velocity by about the square root of that number.


----------



## Henry the Hermit

Kerry Cornelius said:


> What size tubes are you using. I would like to use your design. (Copying is the highest form of complimenting!!! LOL)
> 
> "So, what a coincidence that our band measurements are so close."
> 
> Great minds think alike!
> 
> "What would be the best way to tie off the short loop?"
> 
> I use black waxed string that I buy from my local leather shop. It's roughly the same diameter as the cotton kite string I used to buy, but much stronger.
> 
> Now for the good news.
> 
> *I did it!!!*
> 
> 
> 
> 
> 
> 
> 
> 
> chrony-300-01.jpg
> 
> And here are the bands I used. Length of one side 6.5 inches. The loop is just long enough to fit well on the Dankung. BTW, with the amount of shooting I'm doing, the Dankung is just too uncomfortable, so all future tests will be with Mr. Stubby. I've found no difference in performance but a huge difference in comfort.
> 
> 
> 
> 
> 
> 
> 
> 
> looped-single-300fps.jpg
> 
> Now for some BBs.


All these tests were made with 2040 or 1842 tubes, available from dankung.com or TrulyTexas.com Pre-made tube sets are available from some of our Vendors.


----------



## Henry the Hermit

Carbon said:


> I use a partial butterfly draw when shooting that comes out to 62in or 157cm. I also shoot 3/8" steel (and 5/8" marbles that weigh close to the same) and I'm looking for the right setup.
> 
> I've been using 1745 tubes but they are a little too slow for my liking. I want a FAST setup, something that will turn that 3/8" steel into a penetrating projectile. But I'm a little lost because it looks like Henry's tests were done with a draw that is almost half the length of mine. Should I just scale it up?


For 3/8 steel, 2040 will work best. Stretch the tubes as far as you can and cut them accordingly. I stretch mine to ~600%.


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## jake64

I'm short on rubber right now but could anyone confirm this

i was thinking this could possibly have similar speeds as the double pseudo taper tubes


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## Henry the Hermit

Looks interesting. I may give this a try and post results.


----------



## jake64

look forward to seeing the results


----------



## James Haury

I bought some ss's and some tubes from DX today online should be here in a couple of weeks.


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## lunasling

Gonna give it a go myself!


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## lunasling

Gonna give it a go myself!


----------



## Zachary Fowler

I like the 1745 tubes i dont know what youed call it a 1 third of it looped. I have it set up for a 58 inch draw. I call it my kyudo (samurai archary) slingshot. Its fast.


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## ryanpaul

Henry the Hermit said:


> OK, I know that some of you guys are bored with all the discussion of lb/ft, because velocity is where the glamour is. So here are the results so far, of velocity measurements, from which the energy figures were derived. Note that with 39.7 grain .30 cal lead, pseudo-tapered outperforms looped. The looped configuration doesn't show a clear advantage until projectile weight reaches 125 grains. (.429 lead) I'm guessing that the crossover point is about 100 grains, but don't have any 100 grain ammo.
> 
> 
> 
> 
> 
> 
> 
> 
> avg-velocities.png


hello sir, looks as if 2040 out performs 1842. so you say you wanna make these tubes scream at 600% correct? so what length must tubes be so that 30" is 600% , and how would i figure this?


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## Viper010

30:6=5 you're welcome mate but you may want to go slap your grade school math teacher... Just sayin'


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## ryanpaul

Viper010 said:


> 30:6=5 you're welcome mate but you may want to go slap your grade school math teacher... Just sayin'


oh right the .6 is 60 so the 6 is 600. since you put it that way. thanks.


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## [email protected]

is the Dankung hunting slingshot good for OOT shooting? I'm new to catapulting and wanted to know if this was a good start.


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## mattwalt

[email protected] said:


> is the Dankung hunting slingshot good for OOT shooting? I'm new to catapulting and wanted to know if this was a good start.


Can you post an image of the one you are thing about? If its the one I think it is - then it uses looped tubes in only OTT...


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## SonOfNature

A lot of useful posts. Unfortunately in my country is hard to get latex. Tbg is what i should use, but rotary cutter is hard to find. They are overpriced and cutting mats too.
So 1745 is my choice based on the opinions and tests of members. Today im going to order 10m of tubing. And going to use it on naturals and plywoods. Because of the country is very poor from slinsghot shooting side.


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## pgandy

I haven't tried it but possibly a rotary pizza cutter will suffice. And can be sharpened if needed. As for a cutting mat, a board will do the trick. Ya, 1745 is a good choice.


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## SonOfNature

Ah ok. Maybe once i will try it. Thanks for idea. Now finishing of toddys mule ttf is coming. But how to attach tubes for plywood and ttf ????


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## mattwalt

Mule's quite low - send photos... There are a few ways you could add tubes.


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## SonOfNature

Ok i will try it to send from my home. And want to semi loop the tubes 2:3


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## mattwalt

good choice ;-)


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## SonOfNature

I think a couple of slingshot makers havent got enough time for working with. I want to be a time millionaire ????


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## mattwalt

OK - drill a 4mm hole in the middle of the band groove.

Then you could do a few different attachments (basically you'd have a sideways Toddy tab attachment).

But could also do soft plug.


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## SonOfNature

Which one would you prefer.
Cut a line to the hole attaching the tube or how? Deciding about the best way


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## mattwalt

For me just a hole. I'll try send some photos...


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## mattwalt

Option 1 a + b (the simple option) - you can either pull straight through the frame - or have the tube/s wrap around the edge of the fork TTF - you can also use the matchstick method.










Option 2 (Toddy's paracord tabs) - you can also use Chicago bolts and leather tabs - or simply take the tubes pull trough the hole and slip back over the posts.










Option 3 - snared wrap and tuck - bound wrap and tuck but you loop the binding rubber through the hole and 'snare' the tube before wrapping. Can also simply wrap and tuck.

Option 4 - ball-in-tube (single tube) - basically same as option 1 - but uses a ball inserted in the tube to achieve the same result.

Hope that helps?


----------



## SonOfNature

Exactly. Super. Thank you for the answers. I ve been diciding a lot about the attaching. Pseudo tapering i would make by a piece of tubing at the place where the tubes touching. And make a knot there for sure. 
So a lot of ways to attach tubes. It must arrive from dankung amd finish the catty.
Cheers


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## mattwalt

I use option 1 a lot (on most of my frames - straight through the frame) - pseudo taper works incredibly well


----------



## SonOfNature

Just sanding and sanding while the tubing arrives... [email protected] is a long time from dankung.
But the result will stays for... im sure


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## mattwalt

Odd - I found DK quite quick - less than 2 week (just over one) From China thats quick.


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## SonOfNature

Finised finally, pouch shold be replaced soon


----------



## Blue Raja

Very helpful thread - thank you Henry and all who added to it.


----------



## gunslingster

Very interesting...thank you


----------



## boby

SonOfNature said:


> Just sanding and sanding while the tubing arrives... [email protected] is a long time from dankung.
> But the result will stays for... im sure


Here's what I do for attaching tubes to a wood slingshot: 



 . Wouldn't do it any other way.

By the way, over time I have become disenamored with pseudo-tapered tubes- they break too easily, tend to slip creating uneven sides, and take a lot more time to tie. I prefer a single tube on each side of the fork (1745, 2550, or 2050) and use a stretch factor of 5 (e.g., 30 inch draw for unstretched length of 6").


----------



## europunk

Henry the Hermit said:


> Here are the results of tests on the standard Dankung configuration, i.e. one long tube, looped, with both ends tied at the pouch. This chart clearly shows that at the lighter projectile weights, 2040 is more powerful than 1842. Somewhere between 161 grains and 173 grains, 1842 takes the lead. These figures represent velocities ranging from a high of 267 fps to a low of 119 fps. As a matter of interest, I recorded 302.7 fps with the same .30 cal ball and a pseudo taper 2040 set, proving that more is not always better.
> Maximum recorded power was 17.17 lb/ft.
> 
> Unfortunately, I was unable to find any ammo that weighs 250 grains, so the jump from 205 to 308 is a bit more than I would have liked. Once all my tests are complete, I will make them available. I still have two more band configurations to test.
> 
> View attachment 17156


Mr. hermit. Thank you for all your great research do you have any recommendation for tube set up beer single or tapered or looped tubes to get me to as close to 300 ft./s with 10 mm lead weigh 92 grain. I shoot fall butterfly with a 58 inch fall draw I usually cut my bands to around 12 inches however I am new to two world I currently have some 1632?, And from 1842. Any recommendation would be greatly appreciated thank you so much 

todd


----------



## Henry the Hermit

Hi Todd, I've never shot butterfly, but I believe either looped 2040 or 1842 will get the job done. The key to maximum velocity/power is to stretch the rubber to its limit, draw fast, release quickly. Holding the draw allows the rubber to cool and reduces efficiency. There is wealth of information in the Speed Freaks and Power Rangers Forums.

Henry


----------



## chillwildlife

Finally to round out the doubled 1842 tests I shot .495 balls, calculated weight 175 grains for a 5 round average of 184.4 fps.


----------



## 202

mattwalt said:


> Option 1 a + b (the simple option) - you can either pull straight through the frame - or have the tube/s wrap around the edge of the fork TTF - you can also use the matchstick method.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Option 2 (Toddy's paracord tabs) - you can also use Chicago bolts and leather tabs - or simply take the tubes pull trough the hole and slip back over the posts.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Option 3 - snared wrap and tuck - bound wrap and tuck but you loop the binding rubber through the hole and 'snare' the tube before wrapping. Can also simply wrap and tuck.
> 
> Option 4 - ball-in-tube (single tube) - basically same as option 1 - but uses a ball inserted in the tube to achieve the same result.
> 
> Hope that helps?


I know it’s an old thread but interesting nonetheless.
I like the options presented here.


----------

