full auto Ball Valve design

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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kydavies
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Mon May 03, 2010 10:03 pm

well, this is inspired by a spring trigger system and me accidently breaking off the stopper (part that only lets the ball Valve rotate 90°) on my ¼ inch brass ball valve. i plan on building a prototype with a hand crank andmaby later a spring lever system (drawing in the works) or maby even an electric motor to achieve higher RPM and ROF. please offer any suggestions as this is just a drawing and can be changed
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Ball Valve full Auto explained visually
Ball Valve full Auto explained visually
full auto bb with ball valve.JPEG (25.51 KiB) Viewed 3041 times
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
nosnik
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Mon May 03, 2010 10:09 pm

think a ball valve modded to turn 360 would be safe under the stress of the air pressure ?? unless your using like copper or steel, im not too sure about modding a pvc ball valve :? ( this is just my idea)
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jor2daje
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Mon May 03, 2010 10:14 pm

this has been discussed before here http://www.spudfiles.com/forums/semi-fu ... 18715.html
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chinnerz
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Mon May 03, 2010 10:15 pm

most ball valves of the size you want (maybe 1/4'') are made from metal. there maybe 1 which is plastic, nosnik is right to raise that concern.

also i have had this idea before but havnt posted it as.... well.... i didnt think it would work too well. But here was my plan. taking the motor out of a drill while leaving everything else connected, that way you can spin it fast enough to save at least SOME air for the next shot, and you can get it shooting at a constant speed.
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kydavies
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Mon May 03, 2010 10:20 pm

sorry i forgoti already have a stee ¼ ball valve that the stopper is broken so it rotates 360 and its on my vortex, il go break another one :D and yes its safe enough for me and the motorized version would me my final solution, also i mighthave a problem with the timing of the bbs into the barrel so u could rig some sort of lever system so as the BV spins it feeds a bb just before the Valve opens. :P OFF TO BREAK A BALL VALVE be back in 5
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
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rp181
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Mon May 03, 2010 10:30 pm

You dont need to break it. Just get a metal one, unscrew the handle, and turn it upside down.
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Marffy
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Mon May 03, 2010 10:37 pm

I thought of this before. Never did it because i thought performance would suck. I highly recommend that you have 2 chambers. One is where air will be held and another is the chamber that actually pushes the projectile. Just have them connect by a small tube to reduce the usage of air and make it more efficient. but if you want crazy fast ROF then forget the whole 2 chamber idea.
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Gaderelguitarist
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Mon May 03, 2010 10:47 pm

All I ask is that you make it work and dress t up nicely.

Marffy brings up a good point. Regardless of what pressure and chamber volume you opt for, this solution will eat up air pressure with the first few shots, dramatically weakening all shots to come. You may need to resort to regulated HPA, CO2 or propane in order to keep a somewhat constant chamber pressure.
so many muchness
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kydavies
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Mon May 03, 2010 10:52 pm

ya i might need to resort to co2 but thats not in the budget right now. also i wasnt expecting more than 10 shots to befired off of 1 tank but im still going to give itmy best and let you guys know how its going

BACK TO THE GARAGE!!!!!!!


edit:i made a 5 minute version out of k'nex and popsicle sticks with my spare air chamber and got decent results, now ifi hooked it up to my vortex i would be able to burst fire it quite well
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Ball valve auto.jpg
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
Cannoneer
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Mon May 03, 2010 11:46 pm

I did a ghetto version of this a while back using a ball valve from a super soaker and a 2 litre bottle. At 80psi it got a fair number of shots using 6mm airsoft rounds. Due to the hand crank it wasn't very accurate but it could have been a good Gatling style turret. Although I would use co2 (or propane in my case.) with a large expansion chamber.
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kydavies
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Tue May 04, 2010 12:05 am

yaim going to finish it tomorrow after school and get a small battery operated electric drill from a 2nd hand store or something to makeit more accurate and get a higher Rate of fire and own my friends in airsoft. i can also machine a pully system in the metal shop at school (i mainly build with a hack saw, exacto knife, and duct tape)
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
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jackssmirkingrevenge
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Tue May 04, 2010 12:10 am

Why not have the BBs pass through the ball valve:)
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kydavies
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Tue May 04, 2010 12:14 am

because the ball valve will be spinning fast (i hope), i might just put a gravity fed hopper that holds like 200 bbs so it almost becomes like a vortex but fires in short 1-2 BBs per valve rotation

i cant believe i got this idea by breaking a ball valve with my home made spring trigger! inspiration at its finnest... :idea:
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
Cannoneer
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Tue May 04, 2010 12:15 am

Well Im glad somebody finally decided to take this idea a step farther. It seems to me that alot of people have thought of this but held back because the design called for ball valves. Oh and Im glad to hear that Im not the only one here that has limited tools.
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kydavies
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Tue May 04, 2010 12:18 am

im not that limited with tools but im just lazy and my lazyness has gotten me pretty far (carved half a gun stock with an exacto knife and a hack saw but then gave up causei had better things to do). my dad is a general contractor so i just borrow his tool and all his plumbing stuff :P
mikemurph wrote:yea, the ammo has been changed to a more aero dynamic projectile. it consists of the back half of a dart, and a hot glue ball
AHahahahah!!
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