Yeah, well mine was built for baseball practice for juniors. You know, serves a real purpose. When you bypass the pressure limiting circuit and let it go to 100 psi (about 20 secs) it would blow your _ _ _ _ _ _ _ head off!

Guys, Just an update. I finally got the pressure control circuit working so that as soon as I switch it on, the compressor starts and then auto shuts off at 30psi. This gives the ball a speed of about 35-40 mph which is about right for junior league baseball. As soon as you fire, the compressor ...

Plus, if you have a tiny itty bitty compressor like mine then you can just let it sit while your compressor fills it up over the next 5-10 minutes.
My chamber is 4" by 5.5" and my little 12v compressor blows it up to 35psi in less than 10 seconds. I'ts ready to launch before i've loaded the tennis ...

You didn't say what sort of pump you were after. Hand, foot, 12 volt, 240 volt. I got a 12 volt off ebay for about $60 which blows my chamber up to 35psi in about 8 seconds. That's enough to fire a tennis ball at about 35-40 mph / 60 kph.

Thanks for the complements guys. :D I'll try to answer your questions. First up, I sprayed it blue after my son's team colours. All tube and plumbing are high pressure. The chamber is 95mm ID and the barrel is 65mm ID.
That is a steel elbow from the chamber to the valve. It suited the layout and ...

Here's my first attempt at a pneumatic cannon. I made it to fire tennis balls for my 9 y.o. son to practice baseball. So far I've only wired in the circuits so that the LED flashes along with a buzzer to countdown to the firing of the tennis ball. I've yet to set up the third circuit so the ...