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Unread postPosted: Wed Dec 05, 2007 8:18 pm
Author: Hailfire753
Y'know, I am kinda overcomplicating things by going homemade, but I originally made this thread to display my ideas and collect new ones to build a paintball gun from scratch. I bumped this thread to show a new variant of a recently designed valve.

Part of the reason for this insead of a QEV is the ability to switch between a dedictated auto and dedicated semi-auto modes. Not if-you-pull-the-trigger-fast semi. To be field legal, the gun almost always must have a dedicated semi mode. For home use, or the occasional cheating, I want a full auto gun. In theory this gun would achive a rate of fire greater than 20 bps, faster than the 300 $ tippmann A-5 with e-grip. The DSH valve fires as fast as the hammer can cycle (jack-hammer FAST!) and as fast as the helix mag can load (25-40 bps)

I could use a QEV, as pnuematic-electric markers work (I think?) but there has to be a reason why most paintball guns use hammer valves (besides cost) instead.

I am rather un-knowlagable about QEVs, although I have read the wiki. I assume that QEVs have a fast enough fill and resealing rate for 10 bps?

@ DYI -
DYI wrote:You would need ghetto construction techniques the equal of JSR's to pull this off with epoxy and hardware store materials.
Well, that IS the plan. I may not succeed, but I can try. :wink:

Unread postPosted: Wed Dec 05, 2007 8:50 pm
Author: VH_man
haha yes they can fill/actuate as fast as you want. and to make it full auto, simply add a blowgun and a 125psi pop valve to your pilot assembely. search around and you can see how this works.

if i were you, i would just put a two way ball valve in place. one that goes to the slide valve, another that goes to the saftey pop valve/blowgun. yay select fire!!!!

plus, im pretty sure that at 125 PSI your QEV will propel a paintball well past legal limits. more like 50 PSI is going to be your operating pressure. not only will it be more quiet, your CO2 will last a LONGGGGG time.........

EDIT: btw i should proboably mention a QEV can be piloted by something as small as a schrader and still have extreme power. in fact, a problem with some QEV launchers is that the removal of the bike pump nozzle causes the gun to fire.....

EDIT2: Why not use a hammer valve to actuate the QEV and use the pilot volume to re-cock the hammer valve? i mean, a QEV pilots at nearly a 5psi difference in pilot volume. with a constant airflow to the back of a QEV, if you open up a modified-blowgun sized hole in the thing fast enough it will open undoubtebly, in wich then this air could re-set your hammer. aghhh i might have to draw this up this it too good to pass up.....

EDIT3:my god im editing this alot. here is how to get full-auto with a QEV. remember your most likely going to have an even SMALLER pilot volume than this gun....

http://www.spudfiles.com/forums/viewtopic.php?t=4108&

Unread postPosted: Wed Dec 05, 2007 9:18 pm
Author: Hailfire753
Wow, I seriously never thought of that! Nice idea, I might use it. I think I get what you are saying about the hammer/QEV setup, but a pic would help. And Thanks for the link.

What is the cost of a 3/8 or 3/4 QEV? 50$-75$? links?

Unread postPosted: Wed Dec 05, 2007 9:49 pm
Author: VH_man
at mcmaster a 3/8 inch QEV cost like 15 bucks.........

ill draw the picture up on AUTOCAD because after using it for so long i cant stand using paint for diagrams

Unread postPosted: Wed Dec 05, 2007 9:56 pm
Author: Hailfire753
Wow, are you serious? I was under the impression that they cost a whole lot more. I think I will research QEVs more

Unread postPosted: Wed Dec 05, 2007 11:19 pm
Author: jackssmirkingrevenge
DYI wrote: You would need ghetto construction techniques the equal of JSR's to pull this off with epoxy and hardware store materials.


I'm hurt *sniffle*

:cry:

but you do have a point ;)

Unread postPosted: Wed Dec 05, 2007 11:36 pm
Author: Ragnarok
JSR, no-one but you could create a launcher from nothing but a few offcuts, half a schrader valve and a few ounces of epoxy...

Unread postPosted: Thu Dec 06, 2007 12:46 am
Author: jackssmirkingrevenge
Thanks, but sometimes it's a bit of a bad attitude to have - in the sense that many times, instead of coming up with something then buying the bits I need, I tend to look at what I have first and see what I can make with it, hence the ghetto look :D

Unread postPosted: Thu Dec 06, 2007 12:06 pm
Author: Tom
I think i will make a valve similar to this one, a bit simpler because I don't need a semi-automatic one :D . I'm trying to make a very small valve in length so their wont be much air wasted. Hmm maybe a bolt action .50 caliber sniper :D
Tom

Unread postPosted: Thu Dec 06, 2007 3:25 pm
Author: Ragnarok
jackssmirkingrevenge wrote:Thanks, but sometimes it's a bit of a bad attitude to have - in the sense that many times, instead of coming up with something then buying the bits I need, I tend to look at what I have first and see what I can make with it, hence the ghetto look :D

I tend to come up with a design, change it, then add something, then review it, decide it's pretty good and go and work out a budget, then find that half the pieces are highly expensive or don't even exist, change the design around that, see something someone else did, make more changes, find it's prohibitively expensive, redesign down to a more sensible budget, then get a different idea and start the process all over again.

And that's in between trying to decide what facts about myself will go in this weeks s(t)ig... things that are (sort of) true, but interesting.

Unread postPosted: Thu Dec 06, 2007 5:07 pm
Author: jackssmirkingrevenge
On that note vageuly related note, Chuck Norris can burn ants with a magnifying glass - AT NIGHT!

:D

Unread postPosted: Thu Dec 06, 2007 5:14 pm
Author: Hailfire753
Ragnarok wrote:I tend to come up with a design, change it, then add something, then review it, decide it's pretty good and go and work out a budget, then find that half the pieces are highly expensive or don't even exist, change the design around that, see something someone else did, make more changes, find it's prohibitively expensive, redesign down to a more sensible budget, then get a different idea and start the process all over again.



:P Wow, that is exactly what happened here, and in most of my plans.
Also, nice sig.

Unread postPosted: Thu Dec 06, 2007 5:41 pm
Author: ALIHISGREAT
its a bit random but i was looking at your updated plans and i noticed you plan to use pvc for the barrel. as this will be a sniper i think you should use a proper paintball barrel. I'm not sure how you could attach it and make it work with the feed and blow foreward bolt but i will have a think and try and figure out a way.

Unread postPosted: Thu Dec 06, 2007 5:43 pm
Author: ShowNoMercy
Were is the logic with that? A paintball barrel wont take advantage of the properties of the gun.

Unread postPosted: Thu Dec 06, 2007 6:03 pm
Author: iknowmy3tables
were trying to point you twords more conventional and effective designs like mark's marble mg, only with a blowforward or blowback bolt
http://www.spudfiles.com/forums/full-au ... t4108.html
theres also bcpneumatics' full auto that uses a a sprinkler valve automatically fired by a pressure switch

edit: well it would be more stable since pvc barrels bend but not long enough for homemades you might want to reinforce the barrel with a wooden support or possibly 3/4" sdr21 pvc which should sleeve 3/4"cpvc