[rugerdude]

Okay, so a friend of mine and I built a "spud gun" that we will use to launch confetti and such for an upcoming performance where we will be "playing" (basically acting like we are plating) a song by Rammstein (asche zu asche).

Anyway, we have a nice tank and everything works okay, except we can't get any sort of real pressure. Our solenoid valve won't open if we put more than 80 psi in the tank, and even at that pressure, it's pitifully weak.

Our tank is 4" pvc, and that gets necked down to 1" to go through the valve, and then it goes to the barrel which it 3" PVC.

When we fire it, it won't depressurize all at once, instead it takes a couple seconds to fully discharge (and makes a funny honking noise).

Is the pressure loss because we're necking it down, or is the valve to blame?

Would a butterfly valve work better? Would it be expensive (We've already put 70 bucks into it)?

Thanks in advance!

Sorry to the mods if this ins't gun related enough, but I figure if air rifles are okay...

[darkwing]

Well,
I used a 3" pipe neck down to 3/4 pipe with a ball valve. With a reworked shotgun hull I was able to put a 3/4" ball bearing thru 2 pieces of plywood 1/2" thick with 100psi. Of course the wife didn't know about that. Found a drain blaster at the pawn shop it has a pump mounted to it. It would pump up to 250 psi. Tried it on the sink at 60psi and blew the P trap off not to mention the mess all over the kitchen.

[JesseL]

If I was trying to get really good performance from a pneumatic spud gun, I'd ditch the standard valves altogether and build a plastic rupture disc (http://en.wikipedia.org/wiki/Burst_disc) with a nichrome heater wire attached to the membrane for a trigger.

[hso]

OT for here.

Try http://www.advancedspuds.com/links.htm