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Need Crossbow Trigger Help Answered

I need some help with this heavily modded Reaper, I need a sturdy trigger to fire the crossbow, but that has been proven too difficult for me as I don't have much trigger mech experience. At one point I had it fully working when not loaded, untill it snapped the trigger when I tried to fire an arrow. :P


I don't mean to be annoying but eh...

Technically that device is not a crossbow. A crossbow is a BOW mounted on a stave with a mechanical string release aid.

A bow stores potential kenetic energy in it's elastic LIMBS. The string on a bow ideally does not strech or store any energy like an elastic band.

On this device however, the "bow" is a solid, non moving and non energy storing construction, and all the potential kenetic energy is stored in the elastic string. Therefore this device should be classified as a "catapult" or maybe "balistae". But certianly not a "crossBOW"

I'd suggest even that you would make the "bow" not in a bend backward shape (so that it looks like a bow) but that you make it straight or even make the ends of the "bow" pointing forward so that you have a strong triangle shape to resist the tension of the elastic band. This will mean you will need less K'nex to strenghten the "bow" and thus make a lighter device.

bow_how it works.gif

Thanks for the information, but I knew all of this already. The name is derived from the weapons I made when I was small (12 years old). Back then I would just copy the shape of a crossbow and try to make it work.
This is an outdated 'crossbow' anyway, many other options have been tried after (straight 'bow' fails, outward bend works fine).
It would rather fall into the slingshot category.

can you post instructables for it i rilly wunt to build it to shot my anoying brother?

I did try that....but it has been taken apart weeks ago :P

build your old trigger that worked then ducttape/super glue it

Well it depends on which one you mean...if you mean the rubberband gun trigger...it'll never work...have you ever seen how much strain there is on the arrow? : |

Nope, I meant more like a DrummerIan trigger, ratchet system.

Pff there is nothing wrong with this trigger (see pic). I just want it to connect to the bottom :o

4-arrow trigger 001 (Large).jpg

I never said there was, you asked for trigger help, your trigger is good and fits your gun perfectly, so thats that no more help needed, right?

oh, and whats with all the green connectors on the bow handle?

Those were the only connectors i had left in massive numbers and they are strengthening the handle :P The ones attached to the trigger are really needed for support. And what do you think of this...

4-arrow trigger 002 (Large).jpg4-arrow trigger 004 (Large).jpg

Thats a awesome barrel! I guess it shoots them almost all at the same time. Good stuff, Man!

Did you know these triggers can also be used in a gun? :P
4-barreled BBKWG =3

LOL I did not nitice that before! Did he nick your design?

No of course not...but I was pointing out that you can make 4 of those attached to each other and use these triggers to fire em...Too bad I don't have knex with me or I would've tried it... Maybe you could try it :P

Mabey when my cannon is done.... Im almost finished! Just adding sights and then instructions....

I have really strong one for my crossbow, Ill get pics of it soon.

There is nothing wrong with the trigger.....its just the connection between the parts....and thats just to make it look cool :D