Thanks jackssmirkingrevenge your post is very useful, finally I understand how the equalization hole and the piston works, now i'm going to search the materials to make one piston valve.
it's gonna take me a while make one but, when it's done i'm gonna upload the pictures.

again, thanks for your ...

Hi, I made a stainless steel rod with a spring(20psi) in the end of the rod and works very nice, but i have a problem with the quick exhaust valve part, i dont have any idea how it is inside, i mean; what parts are necessary in order to work as the one of the video?
somebody can send me a internal ...