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Sprinkler Pneumatic Valve in Hybrid ?

Posted: Thu Aug 24, 2006 9:15 am
by sigmounte
Hi !

I'm french excuse my english if it is not perfect , i'm planning on making an hybrid gun , i got some questions about it :

i don't want to use burst disc so i'm thinking about this : eletric valve sending air pressure to a pneumatic sprinkler valve and synchronised with the stun gun

Do you think this is possible ? (also i will use detector to allow the stun gun to shot only if the sprinkler valve have started to open )

Posted: Thu Aug 24, 2006 9:38 am
by Velocity
It has been done (DR used a sprinkler valve on his first hybrid, right?), but honestly, its a pretty bad idea. A SCH 80 union is able to hold much, much more pressure than a sprinker valve, and gives greater flow too. Also, not only is there the possibility that the sprinkler valve will explode, the diaphragm may easily pop as well.

For simplicity, cost (in the long run, I suppose), performance, and safety's sake, just use the union (or cam-locks). The only thing you gain with a sprinkler valve is the ability to fire quicker (due to not having to reload a burst disk)

Posted: Thu Aug 24, 2006 10:04 am
by drac
Faster unless you tear the diaphragm out.. then you're forked.

It would be simpler to have a popoff valve on the sprinkler to actuate at a certain pressure, but the sprinklers still aren't rated to more than 125 (i took mine up to 160 once, but I'm lucky it didn't fail).

Go with a union or cam locks as rmich said.

Posted: Thu Aug 24, 2006 10:04 am
by LucyInTheSky
Wpuld the pressure not just push the diaphram up and fire it without you having to use electrics.

Posted: Thu Aug 24, 2006 3:45 pm
by sigmounte
Ok , you convince me , i will use burst disc , my chamber will be in metal , so i'll use the stainless steel coupling cam lever , so it will allow me an higher pressure than the PVC one ?

Posted: Thu Aug 24, 2006 3:54 pm
by sigmounte
is their a rapid way to make burst disc ?

Posted: Thu Aug 24, 2006 5:02 pm
by Velocity
to make them or to reload them? Either way, no. You could probably easily come up with a way to make burst disks quickly, but to reload them quickly is another story...

Posted: Thu Aug 24, 2006 5:10 pm
by sigmounte
My question is about making them , what do you use ?

Posted: Thu Aug 24, 2006 8:25 pm
by drac
Paper plates are cheap and can be made at a reasonable rate. That or aluminum foil would be my best bet

Posted: Thu Aug 24, 2006 8:45 pm
by M3NT4L
Depends on your barrel or wherever the disk is going to go diameter. Pressures are aswell a factor, low pressure paper then alluminium foil and then my favorite for hybrids alluminium can.

Posted: Thu Aug 24, 2006 8:45 pm
by Velocity
HDPE is what makes the soda bottles, and a circle of HDPE has a bursting pressure of around 150 PSI I think

Posted: Thu Aug 24, 2006 8:46 pm
by huse_spud
i bet if you could get ur hands on a butterfly valve it would work great with a hybrid. i saw a 6" butterfly valve on mythbusters. shot a steel ball like 1/2 a mile using steam power,

Posted: Thu Aug 24, 2006 8:54 pm
by M3NT4L
I know. That was the sickest sht EVER. I convinced my dad to help me with a supersonic all metal (large diameter) helium filled golfball barrel. Why the gb barrel? because i found copper balls that fit perfectly.

Posted: Fri Aug 25, 2006 9:05 am
by sigmounte
Ok after a night without sleeping i think i've found a way to make an Hybrid without burst disc and with instant opening time ( < 1 ms) , with easy loading also

i have to test the method and if i'm still alive in 2-3 day this mean the method is working and i will give the plan here

Posted: Fri Aug 25, 2006 9:58 am
by Jolly Roger
I'm currently in the early stages of designing my own hybrid. I'm building mine just like a piston pneumatic cannon except instead of placing the solenoid valve (sprinkler vlave) at the back of the cannon, I hope to use three 100psi saftey "pop" valves used on steamers etc. Everything else would be the same as a normal hybrid (if I can call any hyrbid normal). This way I won't have to worry about replacing burst disks every round or worry about the safety of the sprinkler valve.