# Medieval Style Slingshot Crossbow?



## JoergS

What would you guys think about a medieval-style crossbow (for shooting balls of course), operated with pretensed rubber instead of the hardened steel spring?

Something like this:

http://js-armbrust.ch/Modelle/Bilder/Occidentalis_Communis.gif


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## harpersgrace

Interesting idea. Will be looking forward to seeing what you come up with,


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## shawnr5

How about a curved bow on the front with the bands attached to the ends and going forward, around bearings, then back to the projectile. It would be like a compound slingshot.


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## Nico

JoergS said:


> What would you guys think about a medieval-style crossbow (for shooting balls of course), operated with pretensed rubber instead of the hardened steel spring?
> 
> Something like this:
> 
> http://js-armbrust.c...is_Communis.gif


I'd like to see that, I am very fascinated with and in search of working medieval style stone crossbows and this would be a cool alternative..

Nico


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## NightKnight

Would love to see it!


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## Aras

actually, I have made a crossbow like this out of lego's with rubber bands


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## Simon Van den Broeck

shawnr5 said:


> How about a curved bow on the front with the bands attached to the ends and going forward, around bearings, then back to the projectile. It would be like a compound slingshot.


Or maybe with arms that swing away from it , to give it more speed .

Simon


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## shawnr5

Simon, if you are thinking along the lines of a ballista, I don't think that you'd get enough stretch out of the bands . You would have to have awkwardly long extensions to get the tension necessary on the bands.


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## Guest

Shawn you should build one. Looks like you have a knack for cad and good ideas.


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## shawnr5

Thanks, Sean. My cave drawings are the result of MS Paint, not any sort of CAD. I have to finish the arrow-shooting slingbow I started several months ago before I even think of building something like this.


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## Charles

JoergS said:


> What would you guys think about a medieval-style crossbow (for shooting balls of course), operated with pretensed rubber instead of the hardened steel spring?
> 
> Something like this:
> 
> http://js-armbrust.c...is_Communis.gif


How would this differ from other crossbow slingshots you have built?

Cheers ...... Charles


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## JoergS

Charles said:


> How would this differ from other crossbow slingshots you have built?


Shorter.
Wider fork (looks like a crossbow "prod").
Rubber is pre-stretched.
Release is a rotating "nut" like in a crossbow.
Long trigger (the "tickler").
Has a stirrup.
Looks like a medieval crossbow.

Enough differences?

Jörg


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## Daniel J

i like the idea of u making a medieval crossbow, but it would be a lot more interesting if used the other idea for the forks in your video about the ballista thing on youtube. because it would be the first time i see one.


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## NoSugarRob

yep, i'd like to see it.


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## Lizard_King

I have allready made it ,,it was funcional but need more work ,,
I used prestreched rubber ,, And you can shot arrows and balls with it ,,
sorry I dont have orginal pictures ,, here is a mspaint scetch I made now ,,
Its very powerfull..







http://i264.photobucket.com/albums/ii189/metallmind/crosbow.jpg
Here is another Fast drawing pitcure







,,
it should look something like that ,,..







http://i264.photobucket.com/albums/ii189/metallmind/samostrel1.jpg

sorry I dont have orginal pitcures of my homemade crossbow with rubber bands ,
hope I could help


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## Charles

It will be interesting to see how it works out. The draw length is very short for a slingshot. The extra elongation of the bands from their front position to their rear position will be very little if the original "bow" arms have significant length. I do not think elastic bands are as "fast" as a bow, so my guess is that it will not have significant power unless the dimensions are changed significantly. But you never know until you try it!

Cheers ..... Charles


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## Lizard_King

Charles said:


> It will be interesting to see how it works out. The draw length is very short for a slingshot. The extra elongation of the bands from their front position to their rear position will be very little if the original "bow" arms have significant length. I do not think elastic bands are as "fast" as a bow, so my guess is that it will not have significant power unless the dimensions are changed significantly. But you never know until you try it!
> 
> Cheers ..... Charles


That is a fast drawing , dont mind dimensions ,,and bad writeing .








The rubber band is prestreched . so you dont need much draw...
I shot with it comercial arrows for crossbow very fast, marbels , and steel balls .


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## JoergS

Black7, that is pretty much the idea.

I started the work on this new weapon, and have finished the lock and trigger part pretty much.

The starting point:










Turned the nut in the lathe, from beech:










Fitted it in the tiller. The hole is for resting the ball in place. I know now you will say "magnet", but I want to shoot lead from it, too.


















Here is the trigger part, to be operated with the looong lever


















Secured the nut with a side plate. The nut can take a lot of force.










Will have to attach the prod (fork) and then take care of the "beauty" part - should be shooting tonite.

EDIT: Charles, I did change the dimensions. Longer draw, more narrow prod. It won't be an exact replica. Functionality rules!

Still, the draw will be a lot shorter than on my other slingshot crossbows. It will be interesting to see how much the prestretching helps.

Jörg


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## Lizard_King

Looking good ..
will you make a Rail that holds the ammo on right derection ? I made it on my crossbow , it's imposible to shot balls without it ..
here is comercial crossbow shotting balls
gG_HB3o8Z9E[/MEDIA]]video


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## JoergS

No. Anything that touches the ammo in flight will reduce speed, potentially harm the rubber and reduce accuracy. The "fork" will be two inches high, so the ball will be lifted up in order to fly straight.

Medieval stone crossbows followed the same principle.

I will use a pouch just like on a normal slingshot. The rails are needed only when you use string. As I don't plan to shoot arrows, I don't need the string.

Jörg


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## Lizard_King

JoergS said:


> No. Anything that touches the ammo in flight will reduce speed, potentially harm the rubber and reduce accuracy. The "fork" will be two inches high, so the ball will be lifted up in order to fly straight.
> 
> Medieval stone crossbows followed the same principle.
> 
> I will use a pouch just like on a normal slingshot. The rails are needed only when you use string. As I don't plan to shoot arrows, I don't need the string.
> 
> Jörg


Ok.. now I get it








you are useing pouche







..
Couze my first try was without the Rail . and the balls were flying all over the place







..
I used the string couze At first it was made as a crossbow to shot arrows, then I added The rail so I can shoot Balls..
prestreched rubber will work just fine... just need to find lenght for maximum power ..
Keep up Good Work ..


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## PandaMan

I know you have probably taken this into consideration, but isn't pre-stretched rubber a bit risky? It could send the projectile right back at you, surely?


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## JoergS

I don't know yet... but will find out.

I see no obvious reason why prestretched bands should do that. Usually pouch entanglement causes backfire. A prestretched pouch won't entangle.

I do see a risk that the ball slips out of the pouch, eventually.

Made the bands this morning. Will use a 60 cm wide "fork", distance from tip to lock is 70 cm - so the bands will be stretched to 75 cm total. I cut the bands to 14 cm each.

Tubular rubber, flat bands would not look cool enough, and I want long band life.

Draw is 12 kg (26 lbs) for the black and 26 kg (57 lbs) for the silver. Tested the lock under that force, no problem.


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## JoergS

Finished it!

Here is the video:






It shoots great, and as you can see in the slomos, the bands never touch anything - they will last a long time.

The weapon is really accurate.


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## Tex-Shooter

Really great. A very nice job. I really like the bow! -- Tex-Shooter


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## Lizard_King

Nice Work , Love it..it would be beautiful when painted..
Didn't think it would be so accurate...
but the ammo is flying just fine..
Keep up the good work ...


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## Jimmy

Great work Jörg, you're an inspiration.


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## Charles

Indeed, with the dimensions as you set it up, the elongation of the bands was quite significant when the weapon is cocked, so you are able to get a reasonable amount of power from it. Bravo!!! Because of the bands, you cannot put the typical stone bow sight yoke in front of the "bow", which is a pity. Have you thought of any sort of sighting system? Some years ago I built a slingshot crossbow and considered putting the bands underneath so the sighting system could be on top without interfering with the bands. But in the end I just put the bands on top as usual. I have seen a slingshot crossbow with the slingshot along the side, in gangstah style, so the sight could be taken over the bands ... but it was not aesthetically pleasing. In any case, you did a nice job ... congratulations!

Cheers ..... Charles


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## NightKnight

Nicely done! I would love to see how much power it could get with Gold bands.


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## Bill Hays

Really nice Jorg.... now present a card edge on, in front of a skull... cut the card and break a pig skull all in one shot with it... the "finesse" and accuracy of a rifle and the power of a "cannon"!


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## A+ Slingshots

Very coo!!!







I could see doubled or tripled tubes on that!!!


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## topher

I wonder whose the strongest crossbow compare to this guys marble crossbow?

http://www.youtube.c...h?v=fW31D-uTZkg


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## topher

JoergS said:


> What would you guys think about a medieval-style crossbow (for shooting balls of course), operated with pretensed rubber instead of the hardened steel spring?
> 
> Something like this:
> 
> http://js-armbrust.c...is_Communis.gif


HERE'S THE HISTORY OF CROSSBOW(The Funny side)


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## e~shot

Just saw the video - Cool Joerg


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## El Topo

Nice handicraft!

Seems to shoot pretty hard!
It would be interesting to see how it works with a modification for bolts or arrows...


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## JoergS

I already made an arrow shooting crossbow. This one is so graceful, I love the free flight of the lead.


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## romanianshadow

The bow construction looks impeccable and really ingenious.  If you were not already a CEO, then you would easily find an engineer or even a carpenter job with your skills!

But I don't think you can get the maximum out of your rubber potential with this design. That's because when using a fork, there are two vectors of force, that are pulling the pouch in two different directions. The ball only follows the resultant of these two forces. The more open is the fork (and the shorter the distance between pouch and fork when extended), the more dissipated are the two vectors, which means the more loss of force. That's why your Christmas Tree project works that well - because there is only a single vector of force that is propelling the projectile directly into the target. 

The only advantage of this medieval kind of rubber based crossbow is that (for sure) it is more noiseless than the others.

Cheers


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## JoergS

romanianshadow said:


> But I don't think you can get the maximum out of your rubber potential with this design. That's because when using a fork, there are two vectors of force, that are pulling the pouch in two different directions. The ball only follows the resultant of these two forces. The more open is the fork (and the shorter the distance between pouch and fork when extended), the more dissipated are the two vectors, which means the more loss of force. That's why your Christmas Tree project works that well - because there is only a single vector of force that is propelling the projectile directly into the target.


What you are saying is true, but don't forget that this design

1) allows me to prestretch the rubber - no dead play at all. With a narrow fork, the wepon would have to be 70 cm longer for the same effect. 5,2 ft vs. 3 ft total length. 
2) allows me to cock the weapon with the stirrup method - much quicker and easier. 
3) avoids noise, but also eliminates rubber damage as there is no hard object that is hit by the bands.

BTW, I finished the soaking in linseed. This brought out the grain and yellowed the color. Nice!

Jörg


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## romanianshadow

It seems that I've missed 3 of the obvious advantages.

In this case, do you think it would be feasible a classic fork pocket slingshot with pre-stretched bands (and maybe a bit wider fork than normal just to allow that) in order to gather some of these advantages? If this can be feasible, it will make the reloading possible at high speed. We'll be able to start with a hand full of balls and deliver shoot after shoot with such a slingshot, am I right?
(I have this idea for some time, but I've never put it into practice because I was just thinking the performance would be too low to deserve the effort)


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## JoergS

That was my idea too, see my related thread in general. Especially if band tearing can be reduced, this would be very interesting.

Strong bands won't work equally well, because gripping the pouch will be hard.


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## romanianshadow

JoergS said:


> That was my idea too, see my related thread in general.


Cool! I will continue the talk there.

Cheers!


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## Nico

Man thats a nice design.. You really are a good craftsman..


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## NoSugarRob

i liked it


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## phoghat

"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing."

Not any more.


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