SpudFiles

This is my first *working* pneumatic. It is my second attempt at a PVC barrel sealer, the first was a dismal failure. I posted a helpme/buildlog here.

The whole thing:

and a cat
no I do not shoot cats

Specs:
This launcher features a 2" barrel sealing piston valve, piloted by a 1" sprinkler valve. The barrel is 120cm of some form of PVC with a 43mm bore (I don't think its sdr21). It fits golf balls PERFECTLY. The muzzle attachment is simply to protect the end of the barrel when I place it on the ground to unscrew the pilot area, plus it looks the part. The chamber is 80cm of 2" pn12 PVC. The pilot area features a male quick connect fitting, so I'm tethered to an air compressor however the launcher has semi auto capability. Right now I just use a bolt/breech loading system, seen below:


The hole is actually from a piston failure, but coincidentally is just the right size for a golf ball.. hmmm. The sleeve is 2" ABS.


The piston is a deodorant can, cut to length. A bolt was epoxied into the end of it, and some PVC was placed inside the cut end and epoxied to reinforce the thin aluminium walls of the deodorant can. The end was then epoxied up. The sealing face is just a neoprene washer.

This is the pilot area:

And disassembled:




I've ordered 60 golf balls off ebay, they should arrive within a few days, then I'll get lots of damage pics/vids. This thing works consistently at 100psi, and is very loud. Its not 100% complete, but as i'm moving into the city to start university soon and cannot take this with me into an urban environment I thought I may as well post it - its as complete as its going to get. I was going to fix the bolt to get a better seal and paint it, but other than that its all done.

KITTEH!

Very nice gun, however, that quick connect fill valve can be dangerous... the pressure srop when you disconect the compressor can set off the piston and fire the gun. Other than that its pretty cool.

Haha looks familiar , nice job looks like a lot of fun with quite a bit of power.

KITTEH!

teh spudgun cat iz watching you ............


jsr is going to kill you for that dead volume... lol I guess all of my guns had smaller chamebr volume than that... so in other words it owuld be a good idea to reduce that a bit as it hampers performance, increases weight and reduces efficiency

Kitteh looks worried your next project might have a bore big enough for it to fit in the barrel

jsr is going to kill you for that dead volume

Yes, he's horrified! I would have put the sprinkler directly behind the pilot chamber and filled through the blowgun. Still, nice effort and I bet performance will be impressive

jackssmirkingrevenge wrote:Yes, he's horrified! I would have put the sprinkler directly behind the pilot chamber and filled through the blowgun. Still, nice effort and I bet performance will be impressive

Aw damn it... I never even considered that option... wow thanks JSR, i shall get down to teh plumberz and find me some threaded adapters and get to work on that. Also doing this might allow me to build some form of PVC stock to make it more comfortable to hold and aim.

thanks again!

Edit:

Gun Freak wrote:that quick connect fill valve can be dangerous... the pressure srop when you disconect the compressor can set off the piston and fire the gun

Initially thats what I thought, so I would always point it in a safe direction when disconnecting the fill. When I was dry-firing it at a gravel pathway it was kicking the rocks up a lot, then when I disconnected it it did not fire, all the air just vented out the male connect. I've tested this a few times, the launcher never fires... I do not understand why

Nice gun. Only question i got is what is that bumper of yours(i think that is what the blue thing is supposed to be).

BTW I Love your pussy, looks a bit like the one i got just mine 5 pounds heavier and half a foot or so longer .

john bunsenburner wrote:Only question i got is what is that bumper of yours

its a piece of hollow pipe, used for air... It came with an air tool kit thing I bought, containing stuff like quick connect fittings, blowgun, teflon tape, etc.

I do not understand why

The massive pilot volume is why..

That breech looks dangerous.It is basically like you intensionally want it to fail there. A big bunch of weak points. every angle is tear waiting to happen.

I don't want to put you down, it's a nice cannon...just remember, safety first...people second..

Brian the brain wrote:That breech looks dangerous.It is basically like you intensionally want it to fail there. A big bunch of weak points. every angle is tear waiting to happen.

Agreed, especially since "The hole is actually from a piston failure" meaning the tears and hairline fractures in the materials are probably already there...

Yeah yeah...parrot all you want...

You failed to spot it first..

Seriously, Jack is right though...that piece of pipe must be covered in hairline fractures and stresspoints.
Replace it or at least re-enforce it by glueing the sleeve over it and then cut a new ( round!) breech hole with another outer sleeve to cover that.

No need to provoke Murphy.

Brian the brain wrote:You failed to spot it first..

In my defence, I was distracted by KITTEH!

As always...

HAHAHA!!

I genuinely lolled