old propane tank (what to do with it)

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SpudFarm
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Mon Jan 28, 2008 10:30 am

hello i was walking around in the garden and spotted a empty 11kg propane tank (like 8 gallon) so i removed the valve and stick a flame over it to remove all propane in there. so what to use it for? they got a pop of valve at 370psi so they take some pressure.

any suggestions?
brother361
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Mon Jan 28, 2008 2:40 pm

umm its kind obiouvos pneumatic potato gun or re fill it wit propane and blow it up
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Killjoy
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Mon Jan 28, 2008 2:43 pm

Pneumatic all the way. 3" porting piston valve with double barrel 2" by 10' long barrels
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DYI
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Mon Jan 28, 2008 4:05 pm

Have to agree with Killjoy here. Get a short chunk of 4" steel pipe, and cut off a threaded end with a few inches extra. Then get it welded onto the tank by a suitably good welder. Then just screw on a a 3 or 4" porting barrel sealing piston valve and 10' - 20' of 3" barrel. Voila! Instant mini-SWAT gun.
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schmanman
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Mon Jan 28, 2008 8:44 pm

yeah, I would have to agree with DIY. :wink:

then put 300 psi in it, and kill some steel plate!
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thespeedycicada
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Mon Jan 28, 2008 9:11 pm

Hybrid? a pneumatics fine but it would be awsome as a hybrid although the opening is small compared to the diameter of the chamber but some cutting and welding should fix that!
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hi
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Mon Jan 28, 2008 11:09 pm

ive seen people make air compressors out of them. you could obviously make a cannon too. i have some old tanks too, maybe i should use one...
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SpudFarm
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Tue Jan 29, 2008 9:54 am

i think of a pumpkin cannon but steel pipe that large is expensive and a that big valve is also really expensive. mabe i just go with a female quick connect to fill my hybrid.
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maxfreke88
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Tue Jan 29, 2008 12:13 pm

a propane tank is made to release it gas slowly. I dont know the effects of the stress from the fast escaping air
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POLAND_SPUD
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Tue Jan 29, 2008 12:20 pm

pipes that large are not only expensive... they are also veeeeeery heavy :D
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SpudFarm
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Wed Jan 30, 2008 12:44 pm

im not to worried about stress. they are made to stand a puncture and hold together with 140psi rushing out for a long time.

and the weight of a cannon that large is not a problem it would have wheels. and if you hold a pumpkin cannon it is probably going to fly out of your hands at 300psi and piston valve.

i can mount a small chamber with a valve between the tank and the small chamber and a piston valve on the other side booth electrically acctuated with some delay first fill from tank then the second open so kinda semi auto.
i may mount my existing piston gun on it so i don't need to build one. but if i have to i will go the coaxial way.

BTW do anyone have an idea of how many shots i will get from the tank if i pressurize a 2" by 10" chamber to 150psi if tank pressure is 300psi?
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POLAND_SPUD
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Wed Jan 30, 2008 2:42 pm

I hope you know you need a reg ? and more important question - how are you going to pressurise that tank? if you are using your muscles to do this it will take you some time.... :roll:
so my suggestion buy yourself a compressor (it doesn't have to be new) or build the same thing as I did: http://www.spudfiles.com/forums/my-comp ... 11866.html....

then you can connect it to the tank

I assume it is going to be cheaper than buying a new regulator....
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SpudFarm
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Fri Feb 01, 2008 8:51 am

what? regulator for air? i got an old 800cc engine lying around and mabe i can make a high pressure compressor of it my current compressor is just 150 psi. but i got a bit of things to do before i jump into something that advanced.
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