SpudFiles

This is a great forum - Loads of info.....
I am obviously a noob and the question is this..
After reading many of the posts and discussions about valves, what would be the best valve for launching a Tennis Ball from 60 - 100MPH = 88 - 150 fps?

If you want any kind of consistency, a sprinkler valve or piston valve would be the best.

you could do it with a ball valve... 60 feet with a tee shirt isnt hard at all. as dyi said, if ou want consistancy then use a sprinkler valve. modded or unmodded. that kinda distance isnt hard to get.

Just put the sprinkler valve between chamber and barell?

No it works best if you put the valve at the end of the barrel...that way when you fire it all the air can escape.


If you have to ask that then you need to read ALOT more.....

nlarson467 wrote:Just put the sprinkler valve between chamber and barell?

Correct, the sprinkler valve holds back the air in the chamber until you open the valve, dumping the air into the barrel and firing the projectile - this is the basic principal of any valve in a pneumatic cannon.

If you want to go above about 75 psi, you NEED pressure-rated parts. Most hardware stores don't carry pressure rated parts. Schedule 40 is not a pressure rating, just a wall thickness - most hardware store sch40 pipe is DWV (Drain-Waste-Vent) which is not acceptable for pressure use. The pipe needs to say "NSF-PW" and a pressure rating (xxxPSI @ 72F) etc.... to be officially rated and safe for use. DWV pipe is OK upto 60-75psi in my (our?) experience. It usually won't blow below 150 but it's not worth risking.
Make sure you know how to solvent weld (clean, prep, prime, glue, set) PVC, and take your time on all your solvent welds.

You might want to consider an over/under design (with the barrel running alongside the chamber, via a U bend) instead of inline, which would allow for a more compact launcher. You also might want to consider a breech loader of some sort.

What will your pressure source be? Bike pump, air compressor? If you intend to use CO2 you'll need a regulator setup, which can get expensive.

Peace,
Pete Zaria.

Thanks Pete Zaria, was not sure I have seen the valve on the side with one end open.

I would like to see the test results from Gepard's suggested configuration, seems maybe he is talking from experience?

I am researching the breach loading now...that is a very attractive option.

Is there a good regulator for air that can be set to a certain pressure and the air line stay open. Say 75 psi and when it gets to that pressure it quits filling chamber?

I would reccomend a piston valve. The just dump loads of air in a flaction of a second.

Tom, I would recommend that you learn how to write a coherent, legible sentence.

All regulators will do what you asked. You set the output for a certain pressure, and it will continue to fill until it reaches that pressure. You can usually buy air regulators in the air compressor section of a hardware store, or at a plumbing supply store. You can also get nice shiny, expensive regulators from a compressed gas supply depot.

Thanks DYI...Nice shiny and expensive........Sounds like wifey

Check out this handy little filler.

http://www.chpower.com/webapp/wcs/store ... &langId=-1

(double post fixed by Pete Zaria - in the future, please use the Edit button to edit/add to your previous post instead of double posting)

DYI wrote:Tom, I would recommend that you learn how to write a coherent, legible sentence.

I think you'll find English is not his first language, to be honest there are Americans on this forum whose level of English isn't far off.

some tennis ball launcher designs, as you can see you don't need an overly complex setup:

http://www.spudfiles.com/forums/my-tenn ... t4516.html

http://www.spudfiles.com/forums/tbs-1-p ... t2323.html

http://www.spudfiles.com/forums/tb-launcher-t2271.html

http://www.spudfiles.com/forums/my-tenn ... t7754.html

http://www.spudfiles.com/forums/keiths- ... t3797.html