SpudFiles

Modderxtrordanare wrote:<snip>, just remember I told you so.

Indeed you did - having made up nearly 20 orings from Oring cord.

Michael

I got it to seal! I used a rubber gasket to seal it against the pilot area. I still need O-rings on my piston though...

Nice clean valve, hope it works as well as it looks!

i really wish i understood and had the time and money to make a nice piston valved gun.

very nice and clean. what do you use for a bumper?

The gasket that seals the back cap on is my bumper. It works pretty well.

I am building a similar valve within a 2" tee, and I also am having trouble with the back plug sealing. If you could direct me to the rubber gasket that you used, I would really, really appreciate it.

Ok, The back plug seals against a short section of 2" pvc pipe in which the piston moves in. The gasket was like 2 1/4" that I got from northern tool and equipment. The hole in the gasket is about 1 3/4" in diameter.

Thanks a lot, I appreciate your help. I have another question if you dont mind answering. My piston is a 1 1/4" endcap, and it is wider than it is long. Therefore, when the piston seats, it is protruding too far out of the short piece of 2" pipe it travels in and it is unstable and may not move back correctly. I cannot lengthen the piston because it will no longer fit in my valve, so i need to remove some of the tee's lip to extend the 2" pipe farther into the tee. Did you have a similar problem, or do you have any ideas? I really appreciate your help.

btw, will moving the barrel farther into the tee restrict flow? Does it need to be centered on the tee's midline?

Yep, I had the same problem. I just dremeled out the side of the T's lip to fit the pipe in farther, but when you remove the lip, the pipe should not fit so tight that you have to pound it in with a hammer, but tight enough to where you can push it in with your hand. I suggest building a valve like dongfang's. Your piston's sealing face I fear is too small, like mine. My valve leaks around the edges of the barrel, and I think it is because my sealing face is too small but I am not quite sure if that is the problem or not. I wish you luck on yours.

Thank you very much for all your help. It would have taken me much longer without all your help. My sealing face is 2 x 2" neoprene washers on top of a 2" fender washer. It is larger than the barrel, and i hope that it will work.

First off, nice valve. Hope you get a gun for it soon!
I'm having a little trouble understanding how you sealed your back cap. Did you sandwich your gasket between the pipe the piston slides in and the end cap? Also, how did you seal your screws? O-rings?
I'm trying to build a valve similar to yours, but can't get the darn thing to stop leaking

Put that on Instructables....