SpudFiles

This is my first piston gun!!!! welcome to the big leagues lol... well not yet because its not done but close enough.

Well i got the parts and put this together this weekend... still cant get the piston to seal quite right yet... Although i haven't glued it together yet and actually tried it at higher pressures. Perhaps you guys have some suggestions.

check pics for more details...

o yea the pipe size...

the barrel is 3/4'' - to shoot paintballs... i have cpvc pipe on there... i know not that great of an idea but i wrapped it in some GORILLA duct tape and i used it on an older gun for a while that just used a ball valve and had no problems. So this new gun is kinda an upgrade for the old ball valve one...

-the chamber is 1''
-the tee connected to the blow gun is 1''
-the 1'' tee is connected to the 1'' coupling... which holds a washer and the bumper for the piston.
-The piston is housed in 1'' pipe and is supposed to seal against 3/4'' inside the tee.

The rubber washer is just about the size of the sealing face, a little bigger... but that's why its not screwed all the way into the piston, so that the area of piston is still exposed to allow air to blow it back once the pilot pressure is dumped via blowgun.

hope this all makes sense, im still working to fix the sealing problem so opinions are welcomed and hoped for!!! otherwise enjoy the cannon... Ill post more pics and damage ones too once its completed.


-charizzard

If the end of the barrel is not smooth, the piston may have trouble sealing it. In one of my piston cannons, I used a dowell with a piece of sand paper glued on the end and used it to "polish" the valve seat nice and flat. It fixed my leak.

Why the enormous pilot chamber?

Why the enormous pilot chamber?

To annoy you

I kept thinking about how big the pilot was. That's really the shortest I could make it. I mean I guess I coulda just put an elbow on there and threaded the shrader through it but a tee seemed like the best idea. And thanks Im gonna try sanding it down when I get home from college. Hopefully that works.


-charizzardd

The valve not sealing is probably because the barrel isn't smooth or the sealing face isn't lined up with it straight.

The huge pilot volume will decrease performance. You could just put a plug in the piston valve tee. Then tap a hole to put a 1/8" or 1/4" tee in the back.

nice gun but why is it in the bbmg show case, congrats on the step up from ballvalves

Pilgrimman wrote:To annoy you

Mission accomplished

charizzardd wrote:I kept thinking about how big the pilot was. That's really the shortest I could make it.

No it isn't, it's at least 10 times bigger than it needs to be and you will see the difference when it comes to power, which is a shame.

pilot volume fail

nice work if you cut down the pilot volume, if nt then you will know to do it next time!