The Internals of a QEV.
Well, Mitch has finally got himself a QEV. Mitch being Mitch, I had to open this baby up and see what was inside. I was always curious how it was different to any piston valve I've built. Exactly the same but just.....perfect. These things really are beautiful In their simplicity. Well worth the money.
Enjoy!
Enjoy!

- Lentamentalisk
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I just love that nice flat black, sexy box QEV! It is so sleek!
I think you have already posted this elsewhere, but where did you get it?
I think you have already posted this elsewhere, but where did you get it?
Do not look back, and grieve over the past, for it is gone;
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
I would have posted a while ago about the website it was on. I only got it a few days ago
.
For a 1/2'', it really doesn't have the flow I thought it had. I don't know if all QEV's are like this, but the port holes are about 8mm in diameter which doesn't at all worry me, I use 6-8mm ammo anyway.

For a 1/2'', it really doesn't have the flow I thought it had. I don't know if all QEV's are like this, but the port holes are about 8mm in diameter which doesn't at all worry me, I use 6-8mm ammo anyway.

- frankrede
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Thats what I was thinking, that style of QEV is jus begging to be beautifully integrated into a stock and a set of weaver mounts put on top of it.Lentamentalisk wrote:I just love that nice flat black, sexy box QEV! It is so sleek!
I think you have already posted this elsewhere, but where did you get it?
Current project: Afghanistan deployment
- jackssmirkingrevenge
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That's something people using QEVs should take note of. If you're using this particular with a 1/2" barrel, you're only getting 40% of the flow you'd be getting from full 1/2" porting like say with a co-axial piston.Mitchza89 wrote:For a 1/2'', it really doesn't have the flow I thought it had. I don't know if all QEV's are like this, but the port holes are about 8mm in diameter which doesn't at all worry me, I use 6-8mm ammo anyway.
Yeah exactly right. I had a feeling this would be the case so I'm glad I got a 1/2''. The flow it has is perfect for what I need.
What worries me is that the piston is like that of a sprinkler valve, just made out of rubber. A lot of QEV's are being taken to pressures that could be bad. There is no way anyone would take a basic rubber diaphragm sprinkler valve up to 400psi when it's only rated to 120-150, so if these are rated the same then why do people take them so high?
What worries me is that the piston is like that of a sprinkler valve, just made out of rubber. A lot of QEV's are being taken to pressures that could be bad. There is no way anyone would take a basic rubber diaphragm sprinkler valve up to 400psi when it's only rated to 120-150, so if these are rated the same then why do people take them so high?

- Lentamentalisk
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Because QEVs tend to be made out of metal, which people are betting their money on holding out past the point at which the piston fails, whereas in a sprinkler valve, the case is made out of plastic, which quite possibly could be weaker than the diaphragm, and nobody wants to be digging little pieces of sprinkler casing out of their aorta.
Do not look back, and grieve over the past, for it is gone;
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
- Carlman
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That is one nice looking but strange qev...
My 1/4" SMC qev from over here with the sand gropers has 10mm flow yet ports to 6mm...
I love the look of it though mate!
My 1/4" SMC qev from over here with the sand gropers has 10mm flow yet ports to 6mm...
I love the look of it though mate!

Aussie spudders unite!!
- jackssmirkingrevenge
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you could have cast one out of epoxy for less than one tenth of that ;PCarlman wrote:I payed 50$ for mine though
- SubsonicSpud
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That is the same style QEV I am using, from www.bellpro.net
I have been using the 1/4 sized one and it also has the same sized porting, the piston they use in the 1/4 and 1/2 I believe is the same. As for the pressure rating, it will have no problem going up to 400psi, the casing is very solid. The piston on mine has not got any damage on it yet, and it has been cycling 10 times a second at up to 15-20Bar in my QEV Popoff setup. After seeing how simple the layout is, I would not think it would be much trouble to make one with only a drill press and a block of plastic or aluminium. The only difficult part would be the piston, which is probably available as a spare part.
SubsonicSpud
I have been using the 1/4 sized one and it also has the same sized porting, the piston they use in the 1/4 and 1/2 I believe is the same. As for the pressure rating, it will have no problem going up to 400psi, the casing is very solid. The piston on mine has not got any damage on it yet, and it has been cycling 10 times a second at up to 15-20Bar in my QEV Popoff setup. After seeing how simple the layout is, I would not think it would be much trouble to make one with only a drill press and a block of plastic or aluminium. The only difficult part would be the piston, which is probably available as a spare part.
SubsonicSpud