# Confused about dankung tubing sizes,



## Rayshot

Hi guys, some feed back please, if you are very familiar with the dankung tubes. Not just knowing the numbers but actually in hand and on the catty.

I have recorded the supposed tube pull caparisons in their supposed order.

If I have done my calculations correctly to find rubber thickness, something doesn't seem to add up with the sizes and each ones rubber thickness, (not diameter thickness) with what I have, or should have received. HOW I CALCULATE; Outer diameter, minus inner diameter, divided by 2= wall thickness (rubber thickness)

A main issue is it is nearly impossible to measure accurately to know if they were labeled correctly, which I swear the 1745 and 2040 were on the wrong package according to the label. You see, the 1745 pulled easier than the 2040. What I kept seeing posted, and according to calculations, the 1745 should be the "beefier of the two"

Next, according to the way to determine the sizes; If I compare the heavier pull of the 1745 or 2040 regardless of the labeling I am in disbelief that the 2050 can have visibly so much more thickness in the rubber's thickness. Not outer diameter, rubber thicknesses between the two.

Also if the measurements are that incrementally smaller between the between the "1745" and the 2050 (0.1mm) than the 2040 and the 1745 (0.4mm). Why is it a heavier pull between the two with the supposed smaller wall thickness difference?

What is your experience? And, Or....

Do you think I have gotten shipped incorrect goods, and or mislabeled labeled goods?

Does Dankung ship goods that are close to what you ordered if they are out of what you want? With this question only respond to POSITIVELY known and received incorrect or changed orders. I DO NOT want to hear bashing of Dankung, they have been very accommodating to me, I only want to know if tubing orders are or have been inaccurate in your case.


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## smitty

I have received lots of tubing from Dankung and so far it has been correct. 17-45 has a much harder pull than 20-40for sure. I use 20-40 for targets with 3/8" steel and 17-45 for hunting with 1/2" lead. Maybe you could get with danny and find all the answers you need. I think he is about the most expert on the subject that you will find.


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## dgui

The 1745 for me is real snappy. The 2040 has no real power to speak of I mean for my preference. I just like the tubung to be longer than the premade tubes with pouches attached. Too short at least for me.


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## crazyslingshot

never has this issue, 1745 is much harder pull than 2040.

4-1745 is awesome. 8 strand 2040 is even better than 4-1745.

But making 8-strand tubing band is difficult for me

then I choose 4-1745.

btw, no need to measure, just watch and compare two tubings, the bigger one is 1745,the smaller one 2040 if you don't have other kind of tubing


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## Rayshot

crazyslingshot said:


> never has this issue, 1745 is much harder pull than 2040.
> 
> 4-1745 is awesome. 8 strand 2040 is even better than 4-1745.
> 
> But making 8-strand tubing band is difficult for me
> 
> then I choose 4-1745.


So guys, do the sizes in look right? SEE PICTURE ABOVE I believe the smaller ones would be correct, 2040 & 1745), Yes? by the looks. But I never purchased it prior to these so I have no definitive basis to compare with. Also does the big tube like like 2050 to you?


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## SPAMBOT

A bit of a necropost, I know.
The reason for 2050 tubes being a heavier pull than 1745 is because they have a greater amount of material. Forget about wall thickness, it is the total area of latex that matters.

Wall thickness for the tubes in question seems to suggest that there should not be much of a difference between 1745 & 2050.
2040: 1mm
1745: 1,4mm +40% compared to 2040
2050: 1,5mm +50% compared to 2040, +7% compared to 1745

Tube area (outer area minus inner area) paints a whole other picture.
2040: 9,4mm^2
1745: 13,6mm^2 +45% compared to 2040
2050: 16,5mm^2 +76% compared to 2040, +21% compared to 1745

And finally there are differences between latex batches, sometimes it is stronger, sometimes weaker.


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## Wingshooter

Here is the way I look at these things. the tube on the left is 1745 the one in the middle is 1842 and the one on the right is 2040. You can see an obvious difference looking at the ends of them.


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## Jacktrevally

A few months ago, Dankung sent me 3 bandsets which were supposed to be 1745. They were different from the 10m of 1745 I ordered.

After some emails, they maintained the bandsets were 1745 and was similar in size than the 10m of 1745 tubing despite I showed them a photo of the two. They told me it was a visual effect because the amber appear bigger!

Bollocks!

After a few more weeks I ordered 1842, 2040, 2050 and another 10m of 1745.

They replied, No 1842 and 2040 in stock but sent be an 8 strands 2040 to compare with the 2050 and a 2050 set with the 1745.

It happened that they were 2050. A hefty pull compared to the 1745.

I'd more than 5500 shot on the amber 2050 and still going! The same 2050 in black with a similar pouch and loop length goes to 2500 shots before breaking.

I get less than 600 shots on black 1842 and 800 on black 1745.

So if anyone knows where to get amber 1745 and 1842 I'm interested to buy some!


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## lobodog2

You know, they say that the black tubing is performance wise the same as the amber tubing...I wonder if it is. I haven't chronographed the two (1745 4 strand) to see, but I will this weekend. I always thought the amber was snappier.


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## ZDP-189

Rayshot said:


> Hi guys, some feed back please, if you are very familiar with the dankung tubes. Not just knowing the numbers but actually in hand and on the catty.
> 
> I have recorded the supposed tube pull caparisons in their supposed order.
> 
> If I have done my calculations correctly to find rubber thickness, something doesn't seem to add up with the sizes and each ones rubber thickness, (not diameter thickness) with what I have, or should have received. HOW I CALCULATE; Outer diameter, minus inner diameter, divided by 2= wall thickness (rubber thickness)
> 
> A main issue is it is nearly impossible to measure accurately to know if they were labeled correctly, which I swear the 1745 and 2040 were on the wrong package according to the label. You see, the 1745 pulled easier than the 2040. What I kept seeing posted, and according to calculations, the 1745 should be the "beefier of the two"
> 
> Next, according to the way to determine the sizes; If I compare the heavier pull of the 1745 or 2040 regardless of the labeling I am in disbelief that the 2050 can have visibly so much more thickness in the rubber's thickness. Not outer diameter, rubber thicknesses between the two.
> 
> Also if the measurements are that incrementally smaller between the between the "1745" and the 2050 (0.1mm) than the 2040 and the 1745 (0.4mm).	Why is it a heavier pull between the two with the supposed smaller wall thickness difference?
> 
> What is your experience? And, Or....
> 
> Do you think I have gotten shipped incorrect goods, and or mislabeled labeled goods?
> 
> Does Dankung ship goods that are close to what you ordered if they are out of what you want? With this question only respond to POSITIVELY known and received incorrect or changed orders. I DO NOT want to hear bashing of Dankung, they have been very accommodating to me, I only want to know if tubing orders are or have been inaccurate in your case.
> 
> View attachment 3371


I covered this in my blog a while ago. http://slingshotforum.com/blog/11/entry-137-chinese-style-shooting/

To calculate area:

X-section area = area of outer circle - inner circle

e.g. 1745 = (3.14*(4.5/2)^2)-(3.14*(1.7/2)^2) = 13.6mm[sup]2[/sup]

Remember that:
Latex formulation may vary, even from batch to batch
Colour dye may or may not have an effect
Chinese bands are not of close tolerance and may not conform to the number spec
Wall thickness plays a role and the holes are often not centred
Surface texture and band condition has an effect
Temperature may not affect tubes of different thicknesses equally
So _YMMV_!


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## Rayshot

ZDP-189 said:


> Hi guys, some feed back please, if you are very familiar with the dankung tubes. Not just knowing the numbers but actually in hand and on the catty.
> 
> I have recorded the supposed tube pull caparisons in their supposed order.
> 
> If I have done my calculations correctly to find rubber thickness, something doesn't seem to add up with the sizes and each ones rubber thickness, (not diameter thickness) with what I have, or should have received. HOW I CALCULATE; Outer diameter, minus inner diameter, divided by 2= wall thickness (rubber thickness)
> 
> A main issue is it is nearly impossible to measure accurately to know if they were labeled correctly, which I swear the 1745 and 2040 were on the wrong package according to the label. You see, the 1745 pulled easier than the 2040. What I kept seeing posted, and according to calculations, the 1745 should be the "beefier of the two"
> 
> Next, according to the way to determine the sizes; If I compare the heavier pull of the 1745 or 2040 regardless of the labeling I am in disbelief that the 2050 can have visibly so much more thickness in the rubber's thickness. Not outer diameter, rubber thicknesses between the two.
> 
> Also if the measurements are that incrementally smaller between the between the "1745" and the 2050 (0.1mm) than the 2040 and the 1745 (0.4mm).	Why is it a heavier pull between the two with the supposed smaller wall thickness difference?
> 
> What is your experience? And, Or....
> 
> Do you think I have gotten shipped incorrect goods, and or mislabeled labeled goods?
> 
> Does Dankung ship goods that are close to what you ordered if they are out of what you want? With this question only respond to POSITIVELY known and received incorrect or changed orders. I DO NOT want to hear bashing of Dankung, they have been very accommodating to me, I only want to know if tubing orders are or have been inaccurate in your case.
> 
> View attachment 3371


I covered this in my blog a while ago. http://slingshotforu...style-shooting/

To calculate area:

X-section area = area of outer circle - inner circle

e.g. 1745 = (3.14*(4.5/2)^2)-(3.14*(1.7/2)^2) = 13.6mm[sup]2[/sup]

Remember that:
Latex formulation may vary, even from batch to batch
Colour dye may or may not have an effect
Chinese bands are not of close tolerance and may not conform to the number spec
Wall thickness plays a role and the holes are often not centred
Surface texture and band condition has an effect
Temperature may not affect tubes of different thicknesses equally
So _YMMV_!
[/quote]

Thanks Dan.

I have long since learned that Dankung did send me tubes, incorrectly labeled. What a pain in the butt when I was trying to make tube sets in conjunction with my 1/2 magnetic BB pouches and couldn't be positive of what I tubing I was selling. Especially after the money I put into the tubes. It didn't break me but was a real monkey wrench in the works.

I have a suspicion with other stories told that Dankung isn't always accurate or on the up and up on what tube is labeled and shipped.

Thankfully a big order with them, subsequent to the above issue, was filled out and labeled correctly.


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## M.J

lobodog2 said:


> You know, they say that the black tubing is performance wise the same as the amber tubing...I wonder if it is. I haven't chronographed the two (1745 4 strand) to see, but I will this weekend. I always thought the amber was snappier.


I would agree with that.


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