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Where can i find a 15mm QEV?

Posted: Tue Aug 02, 2011 12:41 pm
by Goats spudz
i need a 15mm QEV that can be filled via the tank?

Re: Where can i find a 15mm QEV?

Posted: Tue Aug 02, 2011 12:50 pm
by jackssmirkingrevenge
Goats spudz wrote:i need a 15mm QEV...
Here.
...that can be filled via the tank?
You'll need to modify it with a spring behind the piston and a hole in the piston/diaphragm, assuming what you mean is "fill from the chamber side".

Posted: Tue Aug 02, 2011 1:51 pm
by Goats spudz
Image

Posted: Tue Aug 02, 2011 2:10 pm
by jackssmirkingrevenge
It will work but the QEV needs to be modded,Brian's repeater is a good example.

Posted: Tue Aug 02, 2011 2:35 pm
by mattyzip77
Why not put that T that the schrader is in pilot side, saving time and modding???

Posted: Wed Aug 03, 2011 1:27 am
by aEx155
mattyzip77 wrote:Why not put that T that the schrader is in pilot side, saving time and modding???
The only reason I can think of not to do this is because it would increase the pilot volume. (I don't know how good a reason that is though)

Posted: Wed Aug 03, 2011 1:45 am
by jackssmirkingrevenge
aEx155 wrote:The only reason I can think of not to do this is because it would increase the pilot volume. (I don't know how good a reason that is though)
Here's a compromise solution, fit a schrader valve to the blowgun and remove the core. This way, you can fill through the pilot (provided the blowgun is held open) and when you pilot, the flow isn't really restricted. You can improve it further by drilling out the schrader to 4.5mm

Postal cat silencer optional :)

Posted: Wed Aug 03, 2011 12:23 pm
by Goats spudz
jackssmirkingrevenge wrote:
aEx155 wrote:The only reason I can think of not to do this is because it would increase the pilot volume. (I don't know how good a reason that is though)
Here's a compromise solution, fit a schrader valve to the blowgun and remove the core. This way, you can fill through the pilot (provided the blowgun is held open) and when you pilot, the flow isn't really restricted. You can improve it further by drilling out the schrader to 4.5mm

Postal cat silencer optional :)
WoW! i didnt think of that thanks :D

Posted: Wed Aug 03, 2011 12:45 pm
by mattyzip77
@ jack, not what I was thinking exacly, but I like this idea better! When you get to the desired pressure you want, you would just let off of the blow gun trigger and this would close the schrader, correct??? Nice!!!! 8) I like the pussy cat silencer as well!!! :wink:

Posted: Wed Aug 03, 2011 12:49 pm
by jackssmirkingrevenge
mattyzip77 wrote:you would just let off of the blow gun trigger and this would close the schrader, correct?
Not exactly, the schrader in this case is not acting as a valve because the core is removed, all it is doing is providing a connection point with your pump or compressor - but yes, hold the blowgun open until desired chamber pressure is reached, release blowgun, remove pressure source, ready to fire.

Posted: Wed Aug 03, 2011 5:16 pm
by Pneumaticology
Could you avoid modding the valve by having a bleed valve between the HPA tank and a small chamber? The chamber would fill to the PSI of the tank then when fired would begin to slowly refill via the bleed valve. Because it would be at a low pressure for an amount of time would it be sufficient to let the QEV's piston return?

Posted: Wed Aug 03, 2011 8:24 pm
by Gun Freak
No QEV pistons are check valved so even with a spring it wouldn't work.

Posted: Wed Aug 03, 2011 11:08 pm
by jackssmirkingrevenge
Gun Freak wrote:No QEV pistons are check valved so even with a spring it wouldn't work.
Technically it would, it's a complicated equivalent on poking an equalisation hole in the QEV diaphragm.

Also, man who mix epoxy with hands gets stuck in ;)

Posted: Wed Aug 03, 2011 11:11 pm
by Gun Freak
That's way overcomplicated :D
check sig :D

Posted: Thu Aug 04, 2011 12:15 am
by Mr.Tallahassee
waitandbleed.jpg..... Do I see a BFMV fan? :D Very interesting idea though. It might be worth some experimenting. Hmm, money money money.