SpudFiles

Hey guys, so I've decided to spring load the ball valve on my metal pneumatic (WIP). I'm going to try to explain how it works, hope you guys understand. There is a 1.5" barrel, a 1.5" chamber, and a 1.5" ball valve between the two. The ball valve can be locked, and it will be locked closed. There is an extension spring through a hole on the handle of the ball valve and also attached onto the barrel with a pipe clamp. 8)

So here's my question. What should be the general length, wire thickness, and diameter of the spring? Thanks guys.

EDIT: Here's the pipe clamp I'm using.
http://www.grainger.com/Grainger/CADDY- ... Pid=search

the stronger the better.

Stronger than you can cock, so you'll need a lever.

But wouldn't one that's too strong be too hard to pull back and also damage the ball valve when it snaps?
Would this one work or does it need to be stronger? It has a 24 lb load.
http://www.grainger.com/Grainger/Extens ... Pid=search

No, it won't damage the ball valve. A good starting point could be a trampoline spring.

Thanks, I guess I'll use this one
http://www.ebay.com/itm/8-Trampoline-Sp ... 4cfd7e4439

Could I just use the ball valve lever as a lever? If not, how do I make one?

You can, just drill a hole in it, about a third of the length above the actual valve, gives you some advantage on the spring.

I'm sure you can go to Home Depot or a hardware store and buy a good spring, it doesn't have to be a trampoline spring....

I had a 60 pound pull ball valve on one of my launchers, and it was barely enough to actuate the valve, and the valve was a 3/4 inch, so I would recommend an 80 pound pull spring, and extreme lubrication of the valve.

Not all ball valves are created equal, some are easier to turn than others. BTW you should consider a pneumatic piston actuated ball valve.

PotatoEnemy17 wrote:Not all ball valves are created equal, some are easier to turn than others. BTW you should consider a pneumatic piston actuated ball valve.

For all that work he might as well make a piston valve.