I have a can that fits very c good in a 3in pipe. I'm planning on melting some hot glue, and sinking the cut tennis ball into the open end while the glue is still hot. As for the sealing face, you know the puzzle peice like flooring that kids play with? I was thinking the flat side of that will work.

Thanks hubb017, I'm pretty sold on the felt and rubber. And won't a plastic cap break under the pressure? Won't the round shape of the ball affect the sealing?

I can see a tennis ball working. What would you suggest for a sealing face?

I just realized how simple the could be. I'll get a small section of pipe that fits into the t connector, then put some pingpong balls in it, cover on end with some paper, fill it with epoxy, then cut up the inner tube and superglue a few layers to both ends, After removing the paper. Will 3 or 4 ...

Its light grey. An endcap covered in melted rubber could fit perfectly. 1" caps fit EXACTLY into 1.5", I use to use them as ammo. I didn't even need wadding. I'm sure there's a pipe size that comes close enought to free improvise it.

EDIT: I posted that, but forgot to metion that if I can find 1.5 ...

i suggest using 2 pvc end caps that fit inside the pipe u are using with a sealing face and a bumper on the ends. it requires no machining just putting a good sealing face on it. good luck with ur first piston they can be tricky and mine still need some work but thats the design i use. I have a one ...

I need help making my first piston. Most of the existing guides require sheet PVC or O-rings, I have neither. I was planning on making it out of sevral cicular cut-out sections of wood, then cutting up on of the rubber bike innertubs I have lying around, then epoxing it to both ends. Will this work?

Copper. I'm having a hard time even thinking of throwing it out. I already paid for it.

I leaks like crazy and I'm considering building a wooden box to put it in, then pumping it until it blows. I'lll have to do this for every joint, and then I'll use the pvc cement.

Well I just had it at 130 and it dosen't leak or anything. What SHOULD I use? And my apolgies for drwaing this topic so off track from 2" piston valves.

Well I just checked and I was wrong: I have SRD-40

I had no clue that super glue will not work. What would you say the max psi should be?

When did you already answer that? And were using up to 80 psi. We already put super gule in it though

Well it is possilbe that I am not using SDR 21, and I'll start looking for my own answers.

EDIT: I looked and did not find. Is super glue an okay solvent for brass piping? I just bought parts for a marshmellow sniper.

2.5" barrel would be bad as it is rare unless bought online, and fittings are also rare.

A golfball will fit in 1.5" SDR-21 if you are American, or 40mm PN18 PVC if you are Aussie/NZ etc

Well I did find a 2.5in barrel to day, forgot to look for fittings though. A golf ball fill not fit in a 1 ...

This is a great tutorial. I suggest omgimonfrie2 should start simple when he has gained enough knowledge then build a piston valve. It is a great learning process my friend.

I was going with a 2.5 in. barrel until recectly, so a ball/piston valve would be too restreicive. I'm not saying I'm a ...