Page 1 of 5
qev and slide valve semi auto?
Posted: Tue Nov 15, 2011 8:52 am
by lklaussen
Hi, what would be the ideal way to hook up a slide and qev valve for reliable semi auto firing? I'm tryinng to shoot paintballs. What valve size would be the best? Also, is there an easy way to reduce paintball HPA to around 85 or 90 psi?
Thanks a lot.
Posted: Tue Nov 15, 2011 6:18 pm
by POLAND_SPUD
It's isn't very complicated you know.... just get a 1/2" QEV (or 3/4" if you really want maximum performace but mind you you don't really need that for paintball)) and a slide check valve ( 3/8" should be ok though even a 1/4" should do the trick)
check palmers stabilisers
http://palmer-pursuit.com/cart/index.ph ... &cPath=8_9
ohh and for god's sake get a 1/2" to 3/8" bushing... try to limit you pilot volume... sure you can use a bunch of fittings but the gun will be more efficient if you use just one fitting to connect the two
Posted: Tue Nov 15, 2011 10:00 pm
by lklaussen
Thanks! I am thinking about going half inch QEV and i'm not sure about the slide check valve yet. I was looking, but couldn't find anything that wasn't fairly expensive. Any links do decent slide valves that won't break a high schooler's bank?
Anyways, i'm not sure it would work, but I found some fairly cheap 1/8 inch slide valves. Any input on using one of these instead of a larger 1/2, 3/8, or 1/4 inch size? Here's the link to a 1/8 inch one I liked price and cosmetic wise -
http://www.ebay.com/itm/1-2-Inlet-Outle ... 174wt_1193
Also, being new to semi auto firing, I know nothing about QEV's. I found a decent looking 1/2 inch one, but I have no idea if it would work (quality, reliability, airflow, etc...) Here's a link -
http://www.ebay.com/itm/Remote-Coil-Sli ... 1649wt_960
Thanks a lot for all the help! ! !
Posted: Tue Nov 15, 2011 10:33 pm
by Gun Freak
Slide valve from china with fail thread size:
http://item.mobileweb.ebay.com/viewitem ... 2585104637
QEV also from china that looks decent:
http://item.mobileweb.ebay.com/viewitem ... 5964359961
The QEV you linked to should work fine though, I've seen that type be used.
Posted: Tue Nov 15, 2011 10:38 pm
by lklaussen
Awesome, thanks a lot. I like that slide paired with the firs QEV I linked to. With the 33/64 valve, what do you think the best way to cope with size problems?
Posted: Wed Nov 16, 2011 12:29 am
by jackssmirkingrevenge
lklaussen wrote:With the 33/64 valve, what do you think the best way to cope with size problems?
33/64 is roughly half an inch, try and match the diameters on male and female threads of various parts and they should be compatible.
Posted: Wed Nov 16, 2011 12:52 am
by Mr.Tallahassee
I think 33/64 thread diameter is 1/4'' npt. I may be wrong but that sounds about right.
Posted: Wed Nov 16, 2011 12:54 am
by Zeus
Well 33 divides into 64 0.515625 times, so I'd guess it's 1/2 or thereabouts.
Posted: Wed Nov 16, 2011 1:01 am
by jackssmirkingrevenge
Zeus wrote:Well 33 divides into 64 0.515625 times, so I'd guess it's 1/2 or thereabouts.
... but in threaded fittings, the diameter usually refers to the bore, not the thread, so as Mr.Tallahassee pointed out a 1/2 inch or so thread OD probably means what we would call a 1/4" fitting.
Posted: Wed Nov 16, 2011 1:34 am
by Zeus
Ah, I'm reading 33/64 as the nominal size, which as we know is nowhere near the actual size.
Posted: Fri Nov 18, 2011 9:34 pm
by lklaussen
So I wasn't able to get the valves ordered, and I leave for vacation today, so I have some time to contemplate other ways to do efficient semi-auto. I was messing around with a sprinkler valve today, and I had the blowgun empty into another short hose, and connected that to a second blow gun. That way, the diaphragm would only open for the time it takes for the second hose to fill, and equalize the pressure. The second blow gun would let the pressure out of the tube, giving me multiple shots. I did have one problem though, and that was probably because I am only using a one foot length of one and a half inch pvc
Any ideas to get more shots off with the same chamber?
Posted: Sat Nov 19, 2011 1:19 am
by jackssmirkingrevenge
I decided to take one for the team and ordered the following:
http://www.ebay.com/itm/ws/eBayISAPI.dl ... OC:US:1123
http://www.ebay.com/itm/ws/eBayISAPI.dl ... OC:US:1123
http://www.ebay.com/itm/ws/eBayISAPI.dl ... OC:US:1123
The idea is to show that a small bore semi/full auto valve setup is possible for under $20, will keep you posted

Posted: Sat Nov 19, 2011 1:26 am
by lklaussen
Awesome! Can't wait to hear how it goes

Posted: Sat Nov 19, 2011 9:39 am
by Gun Freak
Haha sweet, we will finally know for sure

Posted: Sat Nov 19, 2011 4:31 pm
by POLAND_SPUD
Fiiianally.... don't forget that air cylinders are quite cheap too