4 replies to this topic

[Littlemisterbig]

Hey all,
I just finished reading dartslinger's wonderful thread on airguns, and I found a valve on clipboard that should work, but I'm not sure. It is two way with a normally-closed valve porting. I will post a link to the valve. http://www.clippard.com/part/MJV-2

[Birch]

I think that that valve wouldn't work, because it seems to take in air from where the button is, and it could let air back through that area too. I would suggest using instead: http://www.mcmaster....6790t41/=sfr65z

[rego]

To clear up all of the confusion shown in this thread, I shall offer my expertise. I assume by the valve that your plan for an air gun is to connect the inlet of the valve to an air tank, and the outlet to your barrel. If that is the case, the blaster will work, but most likely with low performance. The important factor is the scfm. This is how much air can flow under standard temperature and pressure when the valve is open. The higher the number, the faster air will be able to build up behind the dart and accelerate it down the barrel. That valve is rated at 25 scfm at 100 psi. Because you will probably be using less than half of that pressure, expect the scfm to drop also. The datasheet from clippard states 14scfm at 50 psi. 14 scfm is way too low for an airgun. Most small quick exhaust valves(1/8-1/4 npt) hover around 100-200scfm. I recommend glancing at Doom's Dirctional control valve actuated qev thread, which shows how to use a quick exhaust valve and 3 way directional control valve together for airguns, a very fine combination used for years by spudders.

TLDR: No it wont work, unless you have another way of using it than described.

Birch, that threading is to mount the valve, not to seal it. The input is on the rear, and the output is on top.

[Nerf Gra]

That is true using it between the barrel and tank but it would function well as a blast button for a backpressure tank.

[rego]

This valve also wouldn't work as a blast button because it would only shut of the supply of air. For a blast button, you need to vent the air on the output to the atmosphere to drop the pressure and actuate the qev/piston valve. You would need a three way valve(directional control valve) in order to do that. The MJVO-3 would be a suitable valve for that.