Blowgun-Triggered Piston Valve

[Jabingo19]

I'm coming up with the basic concept of my next build, a more or less rifle-shaped golf ball gun, and I'm curious if with an efficient enough pilot area I can trigger the piston using just a blowgun and cutting out the unnecessary (in my opinion) cost of a sprinkler valve? Is it possible and I so how tough would it be? Oh and it's a 2" piston valve (contained in 2" tee)

[jackssmirkingrevenge]

It depends how you're making your piston. Close tolerance (epoxy casting, machined, fitted with o-rings) is essential.

2" diameter piston piloted by a schrader, with the benefit of an o-ring seal.

Best thing is to do the math, if you know the flow area of your blowgun and the inner diameter of your tee, you know how loose the piston can afford to be before it doesn't pilot.

[Gaderelguitarist]

Some people on here have made pistons sensitive enough to be piloted by a shraeder valve. Blowguns are very doable. It helps if you have a lathe or drill press to make your piston.

I would suggest using a couple o-rings and a built in check valve in your piston.

Edit: JSR beat me to it by a measly second.

[jackssmirkingrevenge]

It helps if you have a lathe or drill press to make your piston.

... but epoxy casting will give you just as close a fit

[Gaderelguitarist]

Epoxy casting would definitely be easier than machining a block of material to such a tolerance.

Jack, love your lathe as it loves you.

[jackssmirkingrevenge]

Jack, love your lathe as it loves you.

I don't want to forget my volkskartoffelkanone roots either and sound all high an mighty, machining tools are amazing but not essential to make a good quality high performance launcher

[Gippeto]

Sounds something like this one...

Entirely do-able. (click on the picture)




The link

http://www.spudfiles.com/forums/my-firs ... 12796.html

[Jabingo19]

Gippeto the design you linked is almost exactly what I'm doing... Which is weird. Anyways, I do have a lathe, on my older piston gun I bought two flat endcaps and turned them down, problem is that the ID of one of the pipes in my tee housing was actually bigger than the other, so it fit pretty loose at the bottom. But that epoxy idea is really good too, definitely going to make a hybrid PVC end caps and epoxy, thanks.