design for new gun

[spudthug]

ok guys i got inspired today and remembered i had a old fire extinguisher down in my basement...it was packed away because we had like 5 in our house already because someone likes high explosives and gun powder well what i am trying to build is an all metal gun (amg) and have it run at 200 psi...well anyway i need to know what type of valve i should use that would be really fast ( thinking qev but i have no idea how they work...) before i buy one from mcmaster i need to know how they work...how they get activated....or just by the trigger thing that is on the end?? i really have no idea...i am gonna learn how to make pistons if u guys think a qev wouldnt work on this gun....


oh and i was inspired by this ---> http://www.spudfiles.com/forums/viewtopic.php?t=6052& and BTB's all metal guns running at high pressures....



going to watch a show ill be back on here in an hour (mythbusters)

[ShowNoMercy]

You could get a QEV from mcmaster, I think *think* they go up to some high pressures. Or you could get a ball valve they go up to 300psi and activate with a spring loaded design.

[spudthug]

do u know where to get plans for a spring loaded ball valve??? i havent seen one before but i think i know what the look like...post some pics/ diagrams or links but whatver would be better...

[ShowNoMercy]

Umm I know that there is one on this site, I think. The one gun was a wooden stock and had a huge contraption on it, but it used a ball valve and had a trigger to actuate the spring. Lemme check.

How bout this, http://www.spudfiles.com/forums/viewtopic.php?t=3571& ?

[A-98]

dont bother with a ball valve.

and a qev would work, and they are basically a comercial piston valve, just with uber light weight pistons. however, it would have to be layed out in a slightly different way. if that layout is what you want, youll need a barrel sealing piston valve.

[ShowNoMercy]

Can you get an inline QEV or do they not exist?

[spudthug]

wait a-98 what do u mean i would need it layed out in a different way??? diagram please (if u have the time) and i just figured out a problem i will post my new plans (slightly more understandable) then look at them...



EDIT: what are they labelled as at mcmaster because when i put in qev valve it came up pop up qev valves and nothing else...tell me if im stupid

[A-98]

errr...ill see if i can draw it up.

and SNM there are such things as inline qev's, but they are only up to 1/8", or atleast all the ones ive seen.

EDIT: ok here thay are.


the black extension coming out of the black cube(QEV) is the exhaust(barrel) and the part going to the chamber is exactly that, and the pilot goes to the green blowgun. and you fill it from the blowgun side.
if you need more clarification feel free to ask, im bad at comp drawings.

[spudthug]

hey a-98 waht are they labelled as on mcmaster...or should i buy from somewhere else??

[FeLeX]

Man it looks REALLY good so far! Good Luck!

[A-98]

ive updated my above post with diagrams, those three are all ones ive considered building..

i believe its page 413 on mcmaster. ill check and link you. edit it with the links in a sec

EDIT: ok, there are two types that i have found. one is part # 6646K23(enter it in the search feild) on pg 941

the second one i need to find, will edit (again ) it in

[ShowNoMercy]

I am a fan of the third one down, you could easily put a stock on it and it also allows for the mounting of a scope or anything along those lines. Also it makes for a smaller gun while retaining the same features the other two designs have. And with a QEV you could mount the blowgun trigger somewhere it could actually be used as a grip/trigger.

[spudthug]

ok a-98 i want this to kinda look like the gun i got inspired by so i like the look of number one...but how does the blowgun activate it...u dont need to explain ill just go with it does now get over it...but anyway i will draw up my plans again with the qev valves u r gonna link me to then look back in like 15 mins to a half an hour and tell me if they are gunna work

[Scope]

It activates it the same way a blowgun actuates a piston/diapram/or modded sprinkler valve. It lowers the pressure on one side of the piston to make it move letting all the air travel unobstructed through the valve

[A-98]

ok, well, i cant seem to find the second one, but i t was basically the same QEV, just with a 1/4 pilot( vent/fill port). i have some very extensive ideas on the 3rd of my above designs, if you want to attach a stock, however i would have to draw them by hand and scan them in. tell me if you want them, cause i have nothing better to do, but i enjoy free time and if you want more detail on the first design ill also draw that up.

and ill try and find a link for how
QEV's work, cause i could explain, but it would get real complicated, real fast. edit it in a sec.