question on making valves

[jdp204]

hi, im new to pnumnatic cannons and i made my first one this week, a small unimpressive one to me, but my friends little brother thought it was the coolest thing in the world. its just a 3" chamber with a 3/4" barrel with a 4:1 ratio and a ball valve for shooting paintballs and bits of other things.

question part:
anyways, im going to make a far better cannon for myself this weekend and want to use a sprinkler valve. i saw online that i could wire a selenoid valve with some 9v batteries to make it work, but i see you guys mainly have sprinkler valves with "blowguns" coming out of them. why is this? is the blowgun superior to the electric switch? and what is the best valve for use on a higher power unit, i am goign to make a rifle with two barrels, one for shooting golf ball sized object, and a smaller one for airsoft pellets possible or paintballs. i have alot of experience with cannons and an engeneering mind, not too good with spelling though,sorry. please gie me a hand as i would like to have a fun rifle to blast some trees with.

joe.

[jdp204]

as an added note, i got a pvc rocket to go through some plywood at like 40 yards

[spudshot]

well, we put blowguns in there to increase the actuation time of the valve, pneumatically actuating it (using a blowgun) will give you 2X the speed of electric acutaion, also you dont need to keep getting more batteries (that sucks to have to do) the best valve to use on a high power unit? well, the ASCO valves are electric and use 110 for actuation, i've heard good things of them. you could probably mod them too somehow.

have fun and be safe, and use ONLY NSF-PW parts in a pneumatic, DWV and cellular core pipe wont hold, make sure you solvent weld correctly and drill and taps holes where the fitting overlaps the pipe

[jdp204]

thanks, so i can just use the tutorial on this site to make a good valve with a blowgun. and it will give increased performance and seems easier than the electric way. also, i drew a diagram of the cannon i plan to built, only the barrels will lay one on top of the champer and one of the side of it, i just couldnt draw it that way too well. tell me if you think it will work, thanks.

[jdp204]

oops, i guess just copy paste the url because by tag didnt work

also, how does letting air out of the valve make it work better? adn what is the significant gain if any over the electric or blowgun use. thanks.

[BC Pneumatics]

It makes the diaphram pop up, and stop holding back the air. The increase in proformance is very noticable, espetialy on smaller launchers.

[iamthewalrus]

if im using ball valves right now will just using a solenoid instead of a blowgun be significently better then a ball valve??

[jdp204]

yes. and sprinkler valves arent really more expense, as a ball valve can get upwards of 6 bucks.

[boilingleadbath]

Yes, anything's better than a ball vaulve!
2X? I'v heard 'up to 4X'... anyway, it's a BIG differance. A sprinkler vaulve works by letting the air out from behind it. From the box, it opens a tiny hole with a solinoid - when you mod it, you replace the tiny vaulve with a much larger vaulve.

[iamthewalrus]

thanks, also do the threads on pvc fit into the threads of a sprinkler valve, so u can just like use some teflon tape and screw in the pipe to the valve??

[spudshot]

yes the threads from pvc, and the threads from the sprinkler valve are both NPT, which is national pipe thread.

[Andrew52]

and with the blowgun when you fire it its like a trigger which is cool