100% seal, no O-rings!

[hunter1992]

lithium grease works great for lubing rubber. I used this design on my new cannon and it works GREAT! Thanks alot brain!

[pyromaniac]

I am sorry to kick up this topic but does there need to be a equalization hole? i'm trying to make my first piston with this but i just don't see how you will get air to the chamber unless this is a chamber fill piston.

or I'm just stupid.

nvm i get it now.

[origin unknown]

Does the washer in the middle of the piston have 2 holes through it?

[Brian the brain]

The back phram allowes air to pass from the pilot into the chamber.If it doesn't it's not done correctly.
I'd like to see hunter's gun!
I never read his post til now...

[spanerman]

this is exactly how a brittsh QEV works....its like a check valve and seals perfeclty

[Brian the brain]

The back phram allowes air to pass from the pilot into the chamber.If it doesn't it's not done correctly.
I'd like to see hunter's gun!
I never read his post til now...and yes, the middle washer is just for support.
The pham should be kept from turning inside out at pressure it should be supported on the other side by a metal washer like so
pressure----> )I

[dongfang]

Hi,

Add oonnnnnne little disk in the pilot end (like the exit disk, just at the opposite end of the tee, and a little smaller), and you have a DFTV valve. If you want to have one.

That disk should probably be the classic o-ring type, as it should pop into the open, and a tapered oversize disk would be difficult to stuff back into place after each shot.

Regards
Soren

[schmanman]

wow, I've been gone for like amonth and a half, and this thread is still going!

[brogdenlaxmiddie]

Does this clever design work as well, if not better than say other piston valves, specifically ones that use a solid piston?