AMG Fe qev gun!!!!

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
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A-98
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Fri Mar 23, 2007 5:46 pm

ok, ive dug thru all the files that i can find on QEV's and the way you have it set up should work. there is a possibility that the valve is defective, but it doubt it.
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spudthug
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Fri Mar 23, 2007 6:00 pm

yea im gonna switch it around and braze my fitting on to the fe down at my dads shop and i am gonna switch everything there....ill post results in a bit...
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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MrCrowley
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Fri Mar 23, 2007 6:15 pm

Do Not Get It Brazed! When I took mine into to get brazed the guy refused to and said he didn't want me to have an accident he said the brazing can barely hold it at a 100psi let alone for several times and with the weight and strain on the braze and if it gets knocked around a bit. He said come back when I replace the Brass fittings for galv ones then he will weld it which he said could hold upwards of 200psi.Just spend like $3 for a Galv elbow instead of brass and get it welded.
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c19o
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Fri Mar 23, 2007 7:12 pm

I think you should have cyl to the barrel, in to the chamber, and exh to the blowgun. But that's just what I think.
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spudthug
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Fri Mar 23, 2007 7:39 pm

good thing i didnt braze it....i was going to braze it myself and then someone was working at that spot..so i silver soldered it...if u guys dont no what that is...u probly do but basicly its solder on steroids....like 10 pills....its guarenteed to around 2000 psi....so i also fixed my gun and put a quick disconnect on it from my dads shop....ok guys thanks for all the help..and c1 i couldnt do it that way the cyl has to go the the chamber.... its complicated and im not gonna explain it but it has to...when i get to my house ill post pics of it when its polished/painted and such....btw the silver solder melts at 3000 degrees so it ruined the paint job on my tank...ill probly paint the tank black or something....im open to constructive criticism and wahtever suggestions....be on in an hour

mr potato pimp ^_^
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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spudthug
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Fri Mar 23, 2007 7:58 pm

ok guys im back before an hour because i tried the qd valve (quick disconnect) and when i pull off the qd it just dumps the pressure....i was wondering how u r supposed to use a quick disconnect without activating the valve because it is just a straight hole through the disconnect no stop or anything in side....how are u supposed to use them??leave them on and pump running while u fire????
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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MrCrowley
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Fri Mar 23, 2007 8:05 pm

Ball valve after the QD,close the ball valve when filling is complete then disconnect QD from gun. The welding also ruined my paintjob I just went over it with red zinc spraypaint and its as good as new.
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A-98
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Fri Mar 23, 2007 8:08 pm

well the male QD has no sealing mechanism, so you have to A:but a check valve inbetween, B:use a ballvalve, or C: have a female QD hooked up to the gun, and a male to male QD setup and then have that go into the female QD on the compressor. one of the female QD's will go into the gun.

Image

did you ever get it to work? the way you had it originally should have worked. cyl=chamber, in=pilot, exh=barrel
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spudthug
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Fri Mar 23, 2007 9:26 pm

yea exactly thats how i did it...but i screwed something up....idk how but thanks for the help im getting it from my dads shop tomorrow...picks on here original posts tommorrow make sure u look guys
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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Hotwired
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Sat Mar 24, 2007 7:10 am

The QEV is the right way around.

Take the blowgun apart and see if theres anything messing with the seal (unscrew that bit at the back), if it still messes up, take it back and ask for a replacement.

Yes you can take the valve above its rated pressure but if you do then its not the manufacturers problem. I use my QEV at 200psi. I'll try 300 once I get a pump that can do it. Same for the blowgun.

I'd agree with something to prevent air escaping when you remove the pump head from the schrader - the way a schrader is designed is that air WILL leak out when the connection is removed and the QEV will let air out if the blowgun-side pressure drops until the chamber pressure is less than the blowgun-side pressure again.

It looks pretty good but don't scream if people don't post straight away :)
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spudthug
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Sat Mar 24, 2007 7:22 am

ok guys my dads going to pick me up a ball valve at work today and we r gonna hook it up....anyway i picked up some auto primer and candy red paint last night...so i primed it last night and i painted it today...the candy red paint got kinda effed up but it looks pretty good...when its dry ill put the valve on and post here...no pics because my cameras isnt at my dads
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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imablackskater
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Sat Mar 24, 2007 7:26 am

why dont you simply replace the blow gun for a ball valve instead of doing so much
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spudthug
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Sat Mar 24, 2007 7:31 am

what?!?!?!?!? u cant us a ball valve to activate that QEV can you??and anyway u couldnt hook it up to my gun
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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Hotwired
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Sat Mar 24, 2007 7:36 am

All thats needed is a on/off valve to activate it.

A blowgun does that and so can a ball valve. Blowguns look better through :wink:
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spudthug
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Sat Mar 24, 2007 7:36 am

hey guys i want my gun to go to like 250 psi would this fill it up???

http://tngdirect.com/catalog/product_in ... cts_id=363

if not that one how bout this one?? whatever ones better

http://www.safety-devices.com/pump_9815.htm

oh and i need a cheap air compressor because i blew alot of my money on this gun


maybe this one

http://cgi.ebay.com/ebaymotors/250-PSI- ... 5077QQrdZ1
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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