QEV, 3 way valve, slide valve help

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1nxtmonster
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Fri Feb 28, 2014 3:24 pm

But shouldn't a slide valve be balanced? or is it balanced, but just more friction?
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bladeul2006
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Sun Mar 02, 2014 5:36 am

it is balanced, just more pressure on the o-ring seals, so more friction
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jackssmirkingrevenge
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Sun Mar 02, 2014 9:24 am

pressure increases compression on the slide valve o-rings, which increases friction.
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1nxtmonster
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Sun Mar 02, 2014 2:37 pm

Ah. Due to how my trigger is attached to the slide valve, the friction is increased by a leverage force to the point that the return spring won't return the trigger. I then did some experimenting with a flow regulator/restrictor and blowgun valve, the results were way better. At 90 psi I was getting results equal to about 120 psi with slide valve. Plus, the trigger pull is a lot smoother. I'm thinking that I wasn't pulling the slide valve fast enough to get full pilot flow before the qev actuated.

Size is a major issue with a blowgun and tee, so I purchased an inline blowgun that is a lot more compact and doesn't need a tee:
106346s.jpg
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bravootome
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Tue Mar 04, 2014 2:34 am

. Plus, the trigger pull is a lot smoother. I'm thinking that I wasn't pulling the slide valve fast enough to get full pilot flow before the qev actuated.




it means something is wrong with the piston, it doesnt matter how fast you push the pilot. the QEv must respond the same, if it is well done..................
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1nxtmonster
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Tue Mar 04, 2014 4:12 pm

It's a store-bought qev valve.
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Major Collins
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Fri May 09, 2014 3:39 pm

1nxtmonster wrote:Ahhh...how bout this: http://www.ebay.com/itm/MEAD-MV-50-NEW- ... 35c017e55b

Due to size constraints, i'm not sure if it can fit in the gunstock. So I was doing some thinking, and came up with a shut-off valve:
Screen Shot 2014-02-08 at 11.58.18 AM.png
wouldn't this be a better, having a piston with a one way valve?
Image
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