Launcher Problem

[ralphd]

I just finished my first Pneumatic Tennis Ball Launcher. I implemented a barrel sealing piston with an over/under design. To actuate the piston I used an air blow gun. I pressurized it to 80psi and depressed the valve on the blow gun but the piston never moved, all the air escaped from the blowgun instead. The piston is free moving, I checked! Could the problem be I'm not releasing the pilot volume fast enough? Is that why modified irrigation valves are used? Any advice helpful.

[LCTChamp]

What size tee is your piston housed in? If its 3" a blowgun usually won't pilot it unless you have an o-ring seal. Either make a better seal or get a bigger pilot valve.

[ralphd]

It's a 2 inch tee with a 1/4 inch valve.

[inonickname]

Try a larger flow, but I also suspect that a lot of blowguns are only intended to flow in one direction. Also if there are any restrictions such as the quick disconnect you could try removing them for more flow.

[daberno123]

You'll probably need at least a 1/2" ball valve to pilot it, although you may be able to get away something smaller if your piston has o-rings.

[Gippeto]

You can pilot a 2" piston valve with a MODDED blowgun. But I'll admit, the construction has got to be very good.

O-rings on the piston are not necessary though.

This is how I did it on my first piston canon.

[MrCrowley]

Even if you can pilot with a blowgun, I would not recommend it. There would be performance just a 1/2" ball valve away that you decide not to use because of an easier trigger system. And by performance, I mean easily noticeable performance.

If a 1/2" ball valve is too much of an annoyance for you, use a 3/4" or 1" modded sprinkler valve. Like I said before, even if you manage to pilot your piston with a very small pilot valve, congrats, but you are still wasting a lot of performance by doing so.

[ralphd]

Well, a 1/2 ball valve is easy enough. I''ll try to pick one up this weekend. If it works out then my next mod will be the sprinkler valve. Thanks for the help.