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Posted: Sun Dec 26, 2010 11:25 am
by pactin9
al-xg wrote:
Oh I've just realised some of your initial questions weren't answered.
And am obviously partially blind, I hadn't seen the blind two previous posts.


I'd swap the chamber for a length of galvanised steel pipe or something and go for higher pressures.
Using a hammer valve to pilot would be a way of dumping more air with better flow and still have the multi-shot capacity. Basically the larger the Chamber to pilot volume ratio, the more air is dumped per shot (the valve stays open until pressure in pilot volume and chamber are the same, and pressure will drop slower in the chamber due to the larger volume).
I kind of understand where you are going now. Not to sound lazy, but do you think you could link me to a piston valve that would work in my circumstances? Wouldn't I need to refill after the pilot valve releases the first shot? If not, how does the piston get air behind it again? Sorry if I'm confusing two different technologies, you guys have been really helpful so far!

Posted: Sun Dec 26, 2010 4:05 pm
by al-xg
Well you either have quite a large pilot volume on purpose and the hammer valve only releases a part of the pilot volume, the piston stays open until the pressure in the chamber drops to the same pressure as the pilot volume, but a larger volume of air is released through the barrel than though the hammer valve.

Or you could have a spool type 3/2 valve filling the chamber (from another larger chamber) in one position and venting the pilot volume in the other, but the spool valve would be spring loaded and opened by a hammer.

Posted: Sun Dec 26, 2010 11:29 pm
by pactin9
Could you point me to a diagram?

Posted: Sun Dec 26, 2010 11:38 pm
by ramses
You could use a QEV.