Piston problem.

[)DEMON(]

Well, I don't know what I can get to seal my piston right, it has to seal against a odd surface.What can I do Mabey my design isn't right,all I can do now is change the piston and nothing else.

[CS]

What are you using as the sealing face? Yea, your sealing area is weird, but because of the "funnel" shape of the bushing I would think that it would center. What are you using to fill the cannon? Secondly, your equilization point may be to big for your air source.

[jrrdw]

Well after seeing what you have, you could make a new piston with the head sticking slightly inside the barrel and a round rubber washer or big oring rite around the bottem of the inserted part that slides into the barrel. Use the end of the barrel as a guide when building the new piston. Maby??

[saladtossser]

the barrel should stick out of the bushing

[)DEMON(]

I am going to have to experiment with sealing faces I think.I won't put an equilization point because the piston dosn't fit prfectly inside the larger pvc(about 1mm of play).This will also held to seal the piston.What should I use washers or o rings?

[wakkapooo]

I am making a valve almost identical to this one, except chamber sealing. I am using, for the main seal, a "toilet shank ring" or something like that. I've found it fits perfectly with the funnel shape of the bushing. As for the rear end of the piston, I am using a disassembled "test plug." In between is a "cast iron adapter" fitting (PVC), which is just a touch smalller than normal 2" pipe I will post a picture of my prototype piston if wanted.

[)DEMON(]

Thanks,you just gave me a few ideas,I'll be sure to test some of those 'toilet washers'.