custom propane tank

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meatballs
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Tue Jun 12, 2007 7:44 pm

so i had this idea. my propane cannon is awesome, but i dont like how it has this bulky propane bottle on the side. its one of the 14.1oz bottles, not huge but i'd rather not have to use it. and whenever i disconnect the hose to the regulator from the propane tank it has a few shots from the propane in the tubing. so i had the idea that maybe i could have a little propane tank, like some 1/4 or 1/2 inch pipe with end cap/valve on the ends, and fill that with the propane liquid. that would have probably something like forty shots, up to a few hundred, depending on the volume of the tank. so do you think this would work? any suggestions? thanx
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ammosmoke
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Tue Jun 12, 2007 7:59 pm

I don't see why it wouldn't... However, you would probably want to use metal pipe, and you would want to make sure that you put the bottle upside down if you want to get liquid into the pipe.
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chaos
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Tue Jun 12, 2007 8:05 pm

sounds great but i cant seem to remember your gun soz :( can ya link me i cant find it.

anyways for the gun i reckon it would be a great idea just make sure you dont take liquid propane into your gun.

perhaps make the tank into a old backpack that way you wont need a tank mounted on your gun.*

as for the material i suggest metal of a sort i wouldn't trust pvc to hold it over time.*

hope this might help you a bit

peace
~chaos
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meatballs
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Tue Jun 12, 2007 8:16 pm

yes, i would definitely use metal, brass or black iron depending on the size, i guess i forgot to mention that. and the whole idea would be to have liquid propane in the tank, releasing gas into the regulator and the rest of the gun. does anyone know how a blowtorch keeps liquid from coming out? i know they flare up when upside down, but its not like just liquid coming out, its still mostly gas. what keeps the liquid out?
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Fnord
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Tue Jun 12, 2007 8:18 pm

Some 1.5inch copper pipe would work perfectly for this; it's lighter than sch40 iron, won't fragment, won't rust, and takes tempeture changes well.

I was planning on making a custom tank for one of my future guns to make it more portable.

(Edit:Edit: I screwed up my last edit, insert some rambling about a propane torch here)
Last edited by Fnord on Tue Jun 12, 2007 9:15 pm, edited 2 times in total.
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chaos
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Tue Jun 12, 2007 8:42 pm

Yer 1 1/2" copper would be perfect.

ino the whole idea would be to have liquid in the tank but you need to expand that liquid before it goes into your gun. they do this in paintball aswell coz the liquid CO2 can stuff ur gun up.

the torches your thinking about dont let the liquid out because the propane has already expanded into a gas/vapor in the top half of the tank and in the hose.
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ammosmoke
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Tue Jun 12, 2007 8:47 pm

Well, it is probably just because the liquid comes out in a mist. If you have ever shot a green gas can into the air while it is upside down, it will shoot a white fog out. This is the liquid. Nothing keeps the liquid out, it just settles at the bottom, and there is no straw that draws it to the top like a spray can, so it just stays there. As there becomes less and less pressure, more and more liquid turns to gas in there. That is pretty much all that there is to it.
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chaos
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Tue Jun 12, 2007 9:06 pm

ammosmoke wrote:Well, it is probably just because the liquid comes out in a mist. If you have ever shot a green gas can into the air while it is upside down, it will shoot a white fog out. This is the liquid. Nothing keeps the liquid out, it just settles at the bottom, and there is no straw that draws it to the top like a spray can, so it just stays there. As there becomes less and less pressure, more and more liquid turns to gas in there. That is pretty much all that there is to it.
^^ agree thats exactly it, cept spray cans have a straw :wink: turn one upside down n all you get is gas/propellant.
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noname
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Tue Jun 12, 2007 11:21 pm

I'd just use steel. A 1 1/2" nipple a foot long would give you proabably at least half the shots a propane tank would. Copper might be a better material, but it's also $23.99 PER FOOT!
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meatballs
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Wed Jun 13, 2007 3:46 pm

i was thinking maybe even smaller than that, i have a little over a foot of 3/4 inch copper, but i'd like to avoid soldering if i can, i'd prefer threads, so i might stick to a steel nipple. still cant decide tho. and what would you recommend for a valve for putting in the liquid propane?
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Fnord
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Wed Jun 13, 2007 4:12 pm

but it's also $23.99 PER FOOT!
No way. Where do you shop at? 10 feet of 3/4 costs like $20 here, I dont see how 1.5" could cost $24per foot. I mean jeezz.. I would just buy 4 pieces of 3/4" and save a ton.

I would get some conduit pipe if copper is out of the question.
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meatballs
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Wed Jun 13, 2007 5:25 pm

conduit pipe? what's that?
sandman
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Wed Jun 13, 2007 5:55 pm

lol, um exactly what it says, it is pipe that is used as conduit for wires.
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meatballs
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Wed Jun 13, 2007 7:33 pm

why would i want to use conduit pipe for this? like if its meant for use as a conduit, then why would i use it for holding propane under pressure? wouldn't i be better off using brass or steel?
sandman
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Wed Jun 13, 2007 7:55 pm

good question, i was just intreperting what he said, it dosent make much sense to me
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