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hybrid chamber?

Posted: Wed Jan 07, 2009 3:06 am
by Jspellman
I got ahold of two of these these and was wondering if i could maybe use them for chambers on a hybrid? the pressure rating is like 150 or 200 but with a 2.5" or 3" barrel and 3" burst disk do you think it would be able to withstand a hybrid up to like a 4x mix?

Posted: Wed Jan 07, 2009 8:21 am
by JDP12
My initial response is no, that type of tank isn't designed to take the pressure and high shockwave of a hybrid in my opinion. It's also very large, and as with PVC, as the volume gets bigger of the same material, the pressure capabilities go down (think 3/4" pipe and 4" pipe).

If you want try it, just with remote firing, but personally I wouldn't trust it.

My opinion though, someone will probably disagree with me

Posted: Wed Jan 07, 2009 8:53 am
by psycix
6" diameter is really big (for a hybrid chamber). Large diameters cant handle high pressure well unless they've got one hell of a wall thickness.
I would trust it for a 2x hybrid, mayby a tiny it more, but certainly no 4x mix unless you are willing to risk blowing it up with remote firing.

Another note is that on such large tanks there is alot of distance for a DDT runup. And when DDT happens your tank will certainly convert into flying bits of metal.

It would be one hell of a monster cannon though.

Posted: Wed Jan 07, 2009 9:35 am
by Carlman
i dunno thats quite a bead on the caps, normally sugests quite thick metal..

Posted: Wed Jan 07, 2009 9:59 am
by Velocity
Apparently spherical chambers resist detonation better (claim is made <a href="http://www.spudfiles.com/forums/spheric ... l">here</a>), and the stubby nature of this chamber is certainly more spherical than most other hybrid chambers.

Posted: Wed Jan 07, 2009 3:57 pm
by psycix
No, spherical chambers (ignited in the middle) are less prone to invoke detonation as there is a minimal runup distance.

And even then, this tank WILL fail at detonation.
Any tank that can barely hold the pressure at deflagration will certainly fail at detonation.


Multiple spark gaps would help though.

Posted: Wed Jan 07, 2009 4:51 pm
by ramses
i would say that it depends on what the ports are. if you have a 1/4 npt port, you may die. It depends on what you want your safety factor to be; 200psi includes an unknown factor, half it to find the factor after 4x (400psi max pressure for 4x) do you trust it?

keep in mind that it is used, so water from the compressed air (thus the vent on compressors) could have been left in it, rusting the steel, and weakening it.

remote testing, and a bigger port are a must.

Posted: Wed Jan 07, 2009 5:42 pm
by CasinoVanart
I wouldn't trust it, unless a had a group of zombies coming at me and no other options.

Posted: Wed Jan 07, 2009 6:54 pm
by sputnick
I don't know about a hybrid chamber, but I most certainly want one for use with transporting larger amounts of air, never knew you could purchase them separate,

But for my 2 cents on the hybrid idea, I wouldn't do it unless done remotely, I wouldn't even want to monitor that in person, if you could set up a camera or something and get way the hell out of there, then maybe, And besides, unless you know how to weld WELL, how would you put a barrel and everything on that?

Posted: Wed Jan 07, 2009 7:53 pm
by starman
I believe you would fine up to 3x...definitely go with 2 spark gaps equidistant down the length and in the cylindrical center of the chamber. Make it a remote artillery mount though... 8)

Your bigger challenge I think is getting your breech hole drilled/sawed/milled cleanly and strong enough interconnections built with your barrel system and burst disk holder.

You're looking at easy supersonic golfballs with a chamber this large and a 5 - 6' barrel at 3X.

Posted: Thu Jan 08, 2009 10:12 am
by SpudFarm
i have used a 5,5" chamber on 11x with 7mm walls. no sign of stress. in my opinion hybrids is a little over estimated. they are not as brutal as people say.

at 3x this would be completely fine. mabe not as safe as a properly built hybrid so i would not stand on the side of it.

BTW, i do consider to get back to spudding when the snow melts. and i now have a wireless controller with a long range transmitter so i will make a hybrid out of a big compressor tank rated to 180psi and load it harder and harder for each shot. it will have my 20foot golf ball barrel.

a tank like that can get you some info on important things when it fails, not just how high pressure it takes but how it failed. i would say that it gets a hole and gets thrown in one piece a long looong way because of the nature of gasses, they have low density and low bristance. that is the thing that makes them ideal for spudguns, they make much gass but not so fast that it is really hard to contain.

Larda proved this his way pretty well also.