SpudFiles

I have been looking at marble guns for about 4 weeks now and think i am gonna make one. Can I have some basic materials ? And instead of using a bycycle adapter For pumping air in can i use a Basketball minature pump and hook it on for air pumping? well other then that can I have basic intructions?

youll find all you need HERE and HERE

Good luck

The first thing you need to do to start building pneumatics is to get used to you parts. to do this, go to hardware store and make a simple ballvalve gun. Just make sure all your parts are nsf-pw pressure fittings and pipe. It is also important that you use proper primer and cement. Look for the stuff that says "purple primer" and "pvc cement" DONT ask the hardware dudes for cement and primer! Generaly, those guys know less than the good people here at this forum. If you want design ideas, just look around at other peoples guns. Have fun and be safe!

DONT ask the hardware dudes for cement and primer! Generaly, those guys know less than the good people here at this forum

yeah once I asked them when I was a big n00b and i ended up getting pipe joint compound (teflon paste) and even worse I used it

ok tipically we don't tell people plans cause we all belive in designing our own guns but this whole thing is extremmly simple. fist you use tire schrader valves, ball fill valves won't work, and i belive for marbles they take a 3/4" pvc barrel, and the whole thing is [chammber w schrader]--[valve]--[barrel]

I forgot to mention, dont bother with the ball pump. just buy a cheopo "husky" pump by the compressors in Home cheapo.

You probably shouldn't use a basketball mini pump for your cannon because since they are made for basketballs, they can only safely pump anything up to about 15-20 psi, where a cannon would need about 60-100 psi.

Thanks guys! Ok. I pretty much understand the basics but what I can't seem to understand is the pressure chamber. How do I get a bycyle Valve on there without leaking?

~counterstriker!!

well to get a bycycle( ) valve on there without leaking, you drill a hole that is slightly smaller than your threads on the bike valve.. put teflon tape around the threads and thread it in..

Ghetto method-
1.ask for a used bike tire at any bike store
2. cut out the valve
3.get the endcap of ur gun
4.drill a hole that the tube valve will fit through snugly
4. buy jb weld and epoxy it there...

for your valve ill give you a list of valves and info of them

Simplest -greatest to least

1.ball valve
2sprinkler valve
3.QEV
4.burst disk
5.piston



efficiency/performance

1burst disk
2piston
3.QEV
4sprinkler
5ball valve


convenience (price, reload time , ect)

1ball valve
2sprinkler
3piston
4.QEV
5burst disk

Ok, sounds good. But I want something semi small but not a mini.
And how much psi can a pvc resevoir hold?

It depends what the rating is on the pipe. If you get any size sch 40 pvc, you'll be fine. Normally, the valve is the limiting factor for pressure. ball valves are usually 150 psi, sprinkler valves are between 115 and 150.

100 PSI is the safe margin, some people go over that, but just stick with 100.....

the pipe you buy will have a pressure rating. the smaller diamiter pipe the more pressure it can hold. a 2" diamiter pvc reservoir (depending on brand) holds about 200 psi. but like K_I_R said the valve is oftain the limiting factor. this is why home made piston valves are common on high pressure guns, they can hold as much pressure as your pipe

I wanted to make something on the lines of this Is this any good?

bump