The Basics

[kingjames488]

Hi all
I have never really built a pnuematic cannon before.
could someone please tell me the basics as I might be interested in making one.

[ShowNoMercy]

Haha finally you have come to the dark side. A basic pnuematic requires a sealed chamber connected through a valve to a barrel. The chamber can be filled through a schreader valve or with a direct fitting, it depends on what you have. The valve can be a ball valve, preferably metal or a sprinkler valve. Those two are the basic and easiest to use. You fill the chamber up and then open the valve and thus accelerating the projectile. Voila. Much easer than combustions

[Flying_Salt]

Haha finally you have come to the dark side.

Welcome to the dark side We have cookies.

For a first pneumatic, here are the steps:

1) Spend some math classed drawing up random junk you could never build.
2) Take a trip to the hardware store and get the pipe you need.
3) Realize you forgot a lot of stuff, head back to hardware store.
4) Repeat step 3 as many times as needed.
5) Put the whole thing together dry fitted, then realize you can't take it apart.
6) Crack the fittings when you use a mallet to take tem apart.

and so on and so forth...

If you had done some research, you would have found results and information here, here, and here.

EDIT: Maybe you should master hairspray before you move on, because pneumatics tend to be stronger, albeit more reliable.

[ShowNoMercy]

Well I wasnt going to be that harsh, you need to at first draw them in and get them hooked before flaming them. Tsk Tsk

[Flying_Salt]

Yeah I guess spudstuff rubbed off on me. Kingy, I hope you know I'm just playing around. But if you get into the habit of not researching just a little before asking something, then you'll get in big doo-doo with some of the "senior members". (Trust me, it's happened (to me)).

Enough being civil, any plans for the cannon yet?

[ShowNoMercy]

Well first off, what is your monetary status and what are your goals for this cannon?

[Fnord]

For a first pneumatic, here are the steps:

1) Spend some math classed drawing up random junk you could never build.
2) Take a trip to the hardware store and get the pipe you need.
3) Realize you forgot a lot of stuff, head back to hardware store.
4) Repeat step 3 as many times as needed.
5) Put the whole thing together dry fitted, then realize you can't take it apart.
6) Crack the fittings when you use a mallet to take tem apart.

and so on and so forth...

Oh my god flying salt, how do you know exactly what my routine is?!

My steps usually also include:
3) go to hardware store
4) avoid the crabby old lady that tries to find the wrong stuff for you
5) end up not buying half the stuff you need because its overpriced
6) make your own parts and waste tons of epoxy trying to stop it from leaking.
7) realize you spent more on epoxi than you would have on fittings
8 ) throw a tantrum and break the most vital part in the process

welcome to the world of pnuematics kingjames

[kingjames488]

"Welcome to the dark side :Twisted Evil: We have cookies."
I knew this would happen...

well I was thinking a chamber made of 1" steel pipe I think is laying around.
maybe atach that to a 1" ball valve and a 1.5" barrel.

would that work?? because the steel can hold a high pressure...
maybe I'll get $30 and buy one of those 10' lenths of 4"pvc.

[super spuder]

"
well I was thinking a chamber made of 1" steel pipe I think is laying around.
maybe atach that to a 1" ball valve and a 1.5" barrel.

would that work??

that would work.....not very well.... but it would work

[sjog]

What's wrong Scarecrow? Afraid of a little fire.- Wicked Witch of the West

[lukemc]

http://science.howstuffworks.com/spud-gun3.htm

awesome site, it has most of the answers

[GinsuGuy585]

For a nice simple gun:
1.5 ft of 2" pvc
3 ft of 1" pvc
2" endcap
2" to 1" bushing/reducer
1" ball valve
1/2" drill bit
tire valve

All parts must ether list their max pressure (eg. 210psi @ 32C) or say NSF-PW.

Drill a 1/2" hole into the end cap and thread the valve in, locking it in place.
Glue the endcap and reducer to the 2" pipe.
Cut 3" of 1"dia pipe and glue it into the reducer, then glue the ball valve to the other end.
Glue theremaining 1" pipe into the other side of the ball valve.

Use a bike pump and it won't take too long to get decent pressures. Most wooden broom sticks will fit nicely with a little duct tape wrapping. Also corn cobbs, acorns, paintballs (loose for a shotgun effect), and water!

[kingjames488]

thanks for the instructions... but I cant find PVC anywhere in my area.
I can use ABS for the barrel right??
But from what I understand it can't be used for the chamber??
is that right??

I was actually thinking of using an old propane tank sitting around as the chamber.

we have many metal tanks around...

[frankrede]

Abs is usually fine for the chamber.
Even the cell core variety abs can be used in your average aerosol combustion

[pyromaniac]

yes frankrede for a ocmbustion but not a pnuematic. frank you knew that but he might not have sorry.

an abs barrel will be fine.