I need help with pneumatic cannons

[03-Z]

ok i have never made a cannon before and im in the process of getting some materials for this cannon---->http://www.instructables.com/id/A-15mm- ... Sniper-Ri/
and i have no idea how to put the air in the cannon. im thinking you have to pump it in with the tire valve but im not sure. If someone can help me it will greatly be appreciated. Oh and if there is a guide to pneumatic cannons can someone post it please? The person who made the tutorila above said that newbies should start with a ball valve. What is that and where are some plans to build one?

Edited by jrrdw.

[jrrdw]

Welcome to Spudfiles. Go through the pneumatic cannon showcase section before you build the above linked instructable cannon. Look at the cannons that use modified sprinkler valves, it is a better 1st build then a ball valve. Also look up MrCrowley's Golf Ball Cannon on instructables, it should be your second build IMO.

[Hubb]

A pneumatic launcher has three parts: A chamber to hold the air, a valve to do the work, and a barrel to throw the projectile. For this to be a first, it sure does have plenty of bends in it. A good start is to have what's called a 1:1 ratio - that is, the chamber and barrel volume is equal.

I would tend to think (just from my experience - and I'm sure I would be disputed on this) that a ball valve is for those who actually have experience enough to know how to use them. They can be tremendously effective valves when used right, but most people just don't know.

To me, the best beginner valve is the sprinkler valve. Check the link in my sig (Hubb Library) on a link to The Sprinkler Valve. In that book, you will find just about anything you need to know about a sprinkler valve. Modifying a sprinkler valve is a good way to learn how piston and diaphragm valves work, and those valves are usually reserved for the more experienced person.

To be honest, though, the best advise I can offer is to just do it.

[03-Z]

thanks guys! REALY helpful!

[Hubb]

BTW - Welcome to Spudfiles.

[Gun Freak]

Here's my first cannon... It sort of goes through how to make it. It's a really basic one, but I would replace my ball valve with a sprinkler valve.
http://www.youtube.com/watch?v=T-cKAL7jd1s

[FighterAce]

For beginners I think a ball valve is better because its cheap, simple and kinda puts things into perspective. But if its available to you and you dont want to fuss around with trigger systems or opening valves manually, a sprinkler valve isnt that bad of an option.

Here's my first cannon... It sort of goes through how to make it. It's a really basic one, but I would replace my ball valve with a sprinkler valve.

If I were you I'd put a trigger system to open the valve. It will increase your guns performance considerably and its not that hard to do if you know the basics.

I would tend to think (just from my experience - and I'm sure I would be disputed on this) that a ball valve is for those who actually have experience enough to know how to use them. They can be tremendously effective valves when used right, but most people just don't know.

I totally agree with you man, and they can be very reliable because simple really is better. I've used them along with my trigger system on all my guns so far and they never failed me.

[Gun Freak]

If I were you I'd put a trigger system to open the valve. It will increase your guns performance considerably and its not that hard to do if you know the basics.

I said that in my post...

[FighterAce]

To open the ball valve not sprinkler valve

[Gun Freak]

Ohh.. I see. That valve is way too hard to open with a spring or anything.

[POLAND_SPUD]

from 'A 15mm Beginner / Intermediate Pneumatic Sniper Rifle'

If you did actually do some reading around, you would know that making a semi auto gun would need a Blow forward bolt or a HEAR valve

Hold down the blowgun trigger quickly and WHAM! When shooting a barrel full of water, keep your feet close together and stand up straight. The recoil is like nothing... honest.

Go on Spudfiles.com and search the forums

hmmm... I guess that doesn't help spudfiles much


BVs have relatively slow opening time when compared with piston/QEV valves (respectively: roughly +80ms and just a couple of ms)

Some people think they are really bad. I guess that can be attributed to the fact that PVC is popular here and they either:
-never used metal BVs (which can open quite fast when compared with PVC BVs)
-they first used metal BVs as pilots on piston valves so they couldn't see that guns utilizing BVs as main valves are not that terrible