Sweet. My design doesn't use a spring to close, it uses air pressure on the small piston side. I am pretty uneducated in this stuff but from what I gather it sealed off the chamber from the barrel with the piston, that was inside the barrel and the ports were in the barrels' breech behind the piston...

Overall, I think this design would be almost simple to make a valve from and the valve would perform good in a pneumatic gun. The design is also handy as it can be upscaled or downscaled easily for use in larger or smaller cannons.

I designed this valve to fit into a pipe, so to be discrete. I'm also pretty confident when I say that if this design is used with a 1" barrel, the air flowing, pushing the projectile out of the barrel will have no restrictions. The flow rate of the air coming out of the valve would probably be no l...

Technician: Well... I see where you get your name from lol. About half the stuff you said I understood, I got the bit about drag from all the holes. I never thought of using oval holes, but they would prove to be most beneficial, although unpractical. Overall I think this design is still going to be...

inonickname: As I said, I haven't been on this site for some time now, I'm not too familiar with anything atm (Solar's eclipse), but thanks for the info. I'm kinda confused with "pilot volume" I'm assuming it's the pressure in, say, a modified sprinkler valve that holds the diaphragm down. If so, th...

inonickname: I'm not sure what I'd call it, I know it's some kind of piston valve, but that sounds good, not that I truly know what it means... maybe you could tell me? :idea: the term "positively acting" has me stumped. lol :D P.S Thanks for the complimant and comments so far Technician1002 and ino...

Technician: Yes, I'd like to see those images please. If I used bigger holes around the outside the holes on the outside would allow more air through than the center port hole, unless the overall diameter of the valve (80mm) is compromised. What I mean is that I found a good ratio for this design. T...

My new valve design. I just spent about an hour writing all the stuff that tells people about my design, then I accidentally clicked back on the internet explorer and, hey presto! it was gone. So if I can be stuffed in the future, I'll tell yous all about it. So ask away.

I got it from bunnings and modified it, there's a guide on this site on how to modify a sprinkler valve like this one

chaos; thnx for the heads up on u knowing how to weld that, but i dont think that i will be able to do that, of corse i could be mistaken so i'll try it sometime. jrrdw; yes i can see where your coming from, that can be solved a number of ways like having the spring like you said, which i probably w...

yer aye, now remember that rod is very thin, about 12mm, and its not a good idea to weld metal that's that small but im sure ill find a way

thats exactly what i was thinking about a couple of days ago, im still thinking about it and i think it will solve the problem, but it brings up a new one too, how the hell would i make a thing like that, all i have in the workshop is a mill, drill press , a lathe and like every hand tool imaginable

yeah the friction is a problem for me too, it has me stumped on what i'm going to do about it, but i don't know if it will matter or not because a havent even made it yet

i think he means the one that actually gives the air to the barrel

That's what the springs are for, and the bit of metal attached to the small piston that stops the big piston moving, the springs are just there to say "the piston will go back to the starting position" because if the springs don't work then i'll have to find something else to send the pistons back, ...