Yes its a necro-post, and I'm sorry, but I had to ask:
How did you modify the QEV to fill from the chamber? I'm looking into a similar firing mechanism like this and I just can't get how it keeps refilling the pilot. I've got a 3/4" QEV with a rubber disk as a piston kind of like a diaphragm which I doubt is moddable, but its still worth a shot asking.
B2TB: sawed-off 35 bar repeater
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Lentamentalisk
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just open it up, and punch a SMALL hole in the diaphragm/piston thing near the edge, in the part between the pilot and the chamber (NOT BETWEEN THE PILOT AND THE BARREL!), and add a very light spring behind the piston, so that it is normally closed.
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.
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Brian the brain
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Thank you.
It's that simple.
I wonder when we'll start seeing this idea in other peoples launchers...
It's taking you guys a while to get with it...
It reseats with a blowgun as the pilot valve as well you know...
It's that simple.
I wonder when we'll start seeing this idea in other peoples launchers...
It's taking you guys a while to get with it...
It reseats with a blowgun as the pilot valve as well you know...
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Zippster
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Wow. I tried the QEV mod just a moment ago and for once something actually works. Thanks for that one, but theres one more piece to the puzzle - the pilot. What did you use to pilot this beast?
Lastly, does the time spent open for the valve affect the power of the shot? That is, to get more power, should one design a pilot that reseats slower to use more air and vice versa, or am I way off?
PS: And at 35 BAR, how strong of a hammer do you use to pilot the thing?
Lastly, does the time spent open for the valve affect the power of the shot? That is, to get more power, should one design a pilot that reseats slower to use more air and vice versa, or am I way off?
PS: And at 35 BAR, how strong of a hammer do you use to pilot the thing?
Proud to be the only kid on my robotics team with pneumatics experience.
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Brian the brain
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You answered your own question: hammer valve
I needed a brass ( heavy)hammer and a pretty strong spring to speed it up.The last bit comes down to just mementum, the spring can;t keep pushing the hammer valve open, so the last bit of hammer swing is not powered by the spring if you get what I mean.
Longer opening of the pilot dumps more gas into the barrel.That is obvious.
But you don't need that much time because after a split second the ammo is out and you are just wasting power.
Imagine your ammo reaching 200 m/s.
That means an average of 100 m/s ( from 0 to 200)
If your barrel is 1 meter long, it will take 1/100th of a second for the ammo to leave.
that's still just 10 milliseconds.
Add another 10 for the valve reaction time ( overestimation!!) and you'd be safe to say you only need a short tap.
If your good with a blowgun you could still get repeatative shots without the effort of building a hammer and hammer valve.
Great news you tried it!!
I needed a brass ( heavy)hammer and a pretty strong spring to speed it up.The last bit comes down to just mementum, the spring can;t keep pushing the hammer valve open, so the last bit of hammer swing is not powered by the spring if you get what I mean.
Longer opening of the pilot dumps more gas into the barrel.That is obvious.
But you don't need that much time because after a split second the ammo is out and you are just wasting power.
Imagine your ammo reaching 200 m/s.
That means an average of 100 m/s ( from 0 to 200)
If your barrel is 1 meter long, it will take 1/100th of a second for the ammo to leave.
that's still just 10 milliseconds.
Add another 10 for the valve reaction time ( overestimation!!) and you'd be safe to say you only need a short tap.
If your good with a blowgun you could still get repeatative shots without the effort of building a hammer and hammer valve.
Great news you tried it!!
Hehe...
Eindelijk iemand overgehaald zen QEV te modden
Eindelijk iemand overgehaald zen QEV te modden
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air soft fan
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jongens, It looks great, works great meaby it is just great. Man BTB way are you so damm good in this stuf.
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Brian the brain
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Without this forum I'd never gotten this far. We all feed off each other. But thanks...you have seen this one right? [youtube][/youtube]
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!