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6mm crossbow project

Posted: Sat May 05, 2007 3:01 am
by jackssmirkingrevenge
Placed in the mini-section because it didn't seem to fit any other category - this is a project I made for school back in 1999, it was my first ever projectile firing device. I was very into model aircraft at the time, you can see this from the materials and style of construction. The design is basically the same as a spring airsoft pistol, but instead of using a coil spring, the power comes from a crossbow style spring made from a bundle of piano wire rods.

I decided to post it now as there seems to be a considerable interest in spring-piston type airguns on the forum at the moment and some might find it a useful reference. It was quite a powerful creation for my first project, it would put a 6mm BB clean through a CD case.

The prototype is a bit dusty from hanging on my wall for so many years and is a bit worse for wear but you can see from the diagrams what it originally looked like. The drawings are self explanatory but of course any queries are welcome :)

Posted: Sat May 05, 2007 3:53 am
by SleekZ
You know jack, you remind me of DaVinci sometimes; the stuff that comes out of your brain is incredible, and you have those scientific diagrams to back it up!

Posted: Sat May 05, 2007 5:05 am
by Insomniac
Hehehe, now all he needs to do is find out how to type right to left, with all the letters backwards :lol:

Does the crossbow still shoot? If it does, is there any chance of a vid? I really want to see it shoot a hole in somthing!

Posted: Sat May 05, 2007 5:15 am
by mega_swordman
Certainly is very innoventive, and very well thought out. I concur, you are like the DaVinci of spudguns. One brilliant idea after another. How's the preformance, or how was the preformance? What sorts of distance could you get?

Posted: Sat May 05, 2007 6:04 am
by jackssmirkingrevenge
Thanks for the feedback guys :)
Insomniac wrote:Hehehe, now all he needs to do is find out how to type right to left, with all the letters backwards :lol:
For the record, the diagrams are drawn in pen-and-ink :P
Does the crossbow still shoot? If it does, is there any chance of a vid? I really want to see it shoot a hole in somthing!
Sadly it doesn't shoot anymore, I had been using bike brake cable as a bowstring but it snapped a while ago and I never replaced it, the wire it has right now is just for cosmetics as it's hanging in my room.

Performance was comparable to a high end airsoft pistol.

Posted: Sat May 05, 2007 6:29 am
by bboymatty
You do come up with some great stuff jack, just for the record how old are you?

this is simply for me to be able to say "oh hes better because hes older" hahah jj

Posted: Sat May 05, 2007 6:54 am
by jackssmirkingrevenge
I'm 24 (yeah I ought to have grown out of spudguns by now :roll: ), but I was 16 when I made this. The thing with this hobby is it's always going to be an evolutionary process, one is always discovering new techniques, materials and design methods - i certainly couldn't do then what I can do now - the key is perseverance, stick with it and you'll get better (though from what I've seen, you're already a fair way along the road :wink: )

Posted: Sat May 05, 2007 7:41 am
by TwitchTheAussie
So basically its a crossbow bb gun? The wire is connected to a plunger of sorts? im just no good with diagrams and the pics are just mad.

Posted: Sat May 05, 2007 10:49 am
by jackssmirkingrevenge
TwitchTheAussie wrote:So basically its a crossbow bb gun? The wire is connected to a plunger of sorts?
Yep. this is how a normal spring-piston air rifle works. In my design, the coil spring is replaced by the bow that is connected to the rear of the plunger.

Posted: Sat May 05, 2007 7:59 pm
by Insomniac
jackssmirkingrevenge wrote:For the record, the diagrams are drawn in pen-and-ink :P
I know that, but I still want to see you type right-to-left.

Posted: Sat May 05, 2007 11:16 pm
by jackssmirkingrevenge
Insomniac wrote:
jackssmirkingrevenge wrote:For the record, the diagrams are drawn in pen-and-ink :P
I know that, but I still want to see you type right-to-left.
*sigh* there you go:

:D

Posted: Sat May 05, 2007 11:29 pm
by iknowmy3tables
when you made this where you aiming for looks, power, or just being diffrent
why did you choose a bow?

Posted: Sat May 05, 2007 11:36 pm
by jackssmirkingrevenge
Mostly just being different as this was a project where originality counted and an ordinary crossbow just wasn't going to cut it.

In practical terms, the bow offers no significant performance advantage over a conventional coil spring, and indeed makes the device bulkier.

Posted: Sun May 06, 2007 2:20 am
by TwitchTheAussie
Still it looks good doing it and thanks for the explanation. Cheers :P

Posted: Fri Dec 28, 2007 5:06 pm
by jon_89
do you remember what size syringe you used?