SpudFiles

I have a 3/4" QEV, and I want to know just how sensitive they are to triggering. I have heard that they are sensitive enough to be tripped by leaky threads, but I want to know for sure. What would you suggest for a pilot valve?

I would suggest using the biggest pilot you can find, remember to keep it ergonomic too. As long as it can be activated easily by one finger- my vote goes to a blowgun, or one of brian the brains snap valves.

Blowguns work fine in general I think.
Still, flow has to be as large as possible. I fired my first pneumatic with a bicycle valve turned loose, and it significantly increased opening time of the QEV. When I left out the valve entirely performance was much better.

You can easily hear if flow is sufficient or not. If it isn't, the time the compressed air uses to escape into the barrel can be noticed. It should be one short, loud bang

Also, slight drops in pressure in the pilot line can set off the QEV totally or partially. When it was set off partially the QEV seemed to resonate, turning my spudgun into some sort of horn

well honking is also possible... IMHO you should use a ball valve either 1/2" or 3/4"

I have a 1.5 inch QEV and my blowgun pilots it well enough. More often than not it fires before the blow gun is all the way open.

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