SpudFiles

Hi all,

This is my first post here, having done some serious lurking

Anyway, built my first pneumatic cannon, after some months of messing around with combustions and cheap unrated PVC

Specs are as follows:

32mm outside diameter barrel
50mm PVC chamber
1/2" QEV piloted by blowgun

And of course a picture:



Also many thanks to my fellow spudding Dutchman Brianthebrain, without his assistance it would have taken me a lot more time to built his thing...

gun is great but im very impressed you took the time to search instead of asking for us to spoon feed you.Apparently thats hard for most people.
Thanx

looks clean and deadly nice job for your first gun

and ya, thanks for taking the time and using common sense to do some research lol
again, nice work!

--sthorne

A great cannon is made all the better by a quality first post. I too was a lurker... I did not post anything until 6 months later, where I submitted a dual piston valve pneumatic. Anyways, great job; have fun with it.

nice!


I lurked for a couple months, on this forum and many others.

then I gathered my knowledge, and posted my first cannon, which many of you have heard of.

-it's called the "S.W.A.T gun"

Very nice much better than my first although my first sucked.
My only complaint is that the 1/2in QEV may be constricting flow a little a 3/4in one would of been better but it wont affect performance to much.

I was a lurker also I roamed around here for a couple of months never planning to join but one day I had a question and couldnt find an answer and joined.
Again I am very impressed that this is your first.
And what kind of power do you get and what do you pressurize it to.

Nice nice!
How does it perform?

Ook nederlands neem ik aan?
Heb je de qev via BTB gekocht?

Lurker, not me man. I beleave in asking questions, it's what brings out the know how. You got any damage pics? You see, I ask questions and aint affaid to do so! <a href="http://plugin.smileycentral.com/http%25 ... /page.html" target="_blank"><img src="http://smileys.smileycentral.com/cat/3/3_3_2v.gif" alt="SmileyCentral.com" border="0"><img border="0" src="http://plugin.smileycentral.com/http%25 ... e.gif"></a>

thespeedycicada wrote:im very impressed you took the time to search instead of asking for us to spoon feed you.

He's been a member at UKSGC for about 6 months now (which does also cater for European spudders). He's made about 20 posts there, but your point stands, because none of them are "spoon feeding" requests - he's done his own research.
Other people also need to bear in mind it's his first pneumatic.

Not to detract at all from the excellent work though, it's just people seem to forget that just because people may not have posted here before that they're a total newb.
I had racked up 1900 posts at UKSGC before I ever posted here, built 25 cannons - and had lurked here for ten and a half months. Which is a very long time, because if I had signed up only when I first posted, my post rate would be second only (I believe) to JSR's at what works out at 9.67 per day. (If you've not noticed, given I've only been posting for three and a half months, I'm exceptionally close to breaking the 1000 marker)

Nice cannon there. I can't really add much that hasn't been said, but it's still very well made.
Have you managed to test it yet? From what you said on UKSGC, I wasn't sure about it.

Thanks for all the positive feedback people

@psycix: Indeed, parts except the pressure PVC are from BTB. Goedenavond trouwens

About testing, I just went out and shot some spuds. However, I made a mistake by not completely removing the valve connected to the blowgun. That greatly increased the opening time of the QEV which led to somewhat disappointing results.

I just tested the thing with the bicycle valve completely removed. Then it gave a quite loud bang when firing (no ammo though).
Well, learned another thing about QEV's...

I have to look into some way of leaving the valve connected and having some manual valve to open the blowgun.

Also, projectiles that seal the barrel can be difficult to push all the way down. I noticed spuds pushing the ramrod back up again. Have to look into that issue later on. Maybe I will also built a breech loading system.

bigbob12345 wrote:My only complaint is that the 1/2in QEV may be constricting flow a little a 3/4in one would of been better but it wont affect performance to much.

I think it would affect performance quite a bit - otherwise, good job

Replace it with a car tire valve and drill out the inner bits so it's hollow.
This way you can pump it up and use it without having to unscrew the insides every time. 8)
I told you it was all I had lying around at that moment.

HOPE YOU'RE HAPPY WITH IT!!


edit: added some smilies...

there's nothing wrong with asking questions...did your moms ever tell you that before school? lol, naa but seriously i like ya gun

Brian the brain wrote:Replace it with a car tire valve and drill out the inner bits so it's hollow.
This way you can pump it up and use it without having to unscrew the insides every time. 8)

I bought a quality bicycle pump with pressure gauge. Now I can get up to 8 bar / ~120 psi. Could go higher, but the sound of pressurised air leaking away from the head that connects to the valve scares me a little bit. With each stroke of the pump the hissing gets louder
-edit- seal with valve not complete... some teflon tape makes the seal better and the pressure easier to monitor.
Manual pumps are a good exercise by the way

I understand what you are saying about the empty schrader or car tire valve, but doesn't the pump need a built in valve to prevent the air from flowing back into the pump?

Also did a test shot with a spud. Niiiice recoil

I also tested my pneumatic as a dust remover. Pump to pressure, point at insides of computer and fire away

TNW_NL wrote:

Brian the brain wrote:Replace it with a car tire valve and drill out the inner bits so it's hollow.
This way you can pump it up and use it without having to unscrew the insides every time. 8)

I bought a quality bicycle pump with pressure gauge. Now I can get up to 8 bar / ~120 psi. Could go higher, but the sound of pressurised air leaking away from the head that connects to the valve scares me a little bit. With each stroke of the pump the hissing gets louder
-edit- seal with valve not complete... some teflon tape makes the seal better and the pressure easier to monitor.
Manual pumps are a good exercise by the way

I understand what you are saying about the empty schrader or car tire valve, but doesn't the pump need a built in valve to prevent the air from flowing back into the pump?

Also did a test shot with a spud. Niiiice recoil

I also tested my pneumatic as a dust remover. Pump to pressure, point at insides of computer and fire away

Having a gauge on your pump is good. That way you dont need one on your gun.
I got such a pump too
BTW, a pump already has a check valve built in so dont worry about the air flowing back

BTW, at what pressure did you blast off the dust?
I could imagine some resistors, capacitors and other parts flying around