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Posted: Sat Feb 14, 2009 9:35 pm
by tape fist
Speaking of which, what are those little blue propane tanks rated to? because I do not want to have to hunt down more free fire extinguisher tanks...
200-250 PSI if were thinking of the same one.
Posted: Sat Feb 14, 2009 9:57 pm
by sputnick
Its not blue, but you get the idea...
They are only about 4 bucks a pop, and come with PROPANE! meanwhile those other ones have about the same capacity, are about 20$ each, and are not a certain pressure. I would actually have a hard time getting rid of the propane since I don't make combustion guns... I could always just get the whole kit and use it to make more copper guns, because everyone loves copper.
How would you go about getting a reasonable flow out of a propane tank? and what kind of threads do they take, because I want to get the check valve out of there, and just hook it right up.
Posted: Sat Feb 14, 2009 10:13 pm
by tape fist
This will give you some useful tips on how to prep the tank and replace the pressure-relief valve.
http://wolfstone.halloweenhost.com/Hall ... rTank.html
Posted: Sat Feb 14, 2009 10:41 pm
by sputnick
Almost helpful
Thanks fist, but that was already some obvious sh|t.
I really wanted to know how I could just drill out the fitting to get rid of all the internals, then just use the original threads so I don't have to do any real work
I do not have a tap and die set, and am strapped for cash, so I am really looking for shortcuts here if anyone has them.
Posted: Sat Feb 14, 2009 11:10 pm
by tape fist
what im getting is that you want to screw a valve strait on to the tank after removing the check valve.I just checked and my 3/4 female bushing screwed tightly on to this propane fuel tank that cost 2 dollars and then you go from there.

hoped this helped and ya it was some pretty obvious sh|t i just didn't know if you new it already.
Posted: Sat Feb 14, 2009 11:16 pm
by sputnick
Sweet mate thanks for the help, and not exactly a valve, but some form of fitting of course. So just 3/4 NPT should be fine? because I wanted to use this as a cheap larger capacity air tank that can be replaced with just a galvanized one when I get a shock pump.
Going to build this shotgun someday
Sorry for the thread hijack by the way everyone...
Posted: Sat Feb 14, 2009 11:28 pm
by tape fist
This is what i screwed on there but ya 3/4 NPT should be fine.I`ve never used a propane tank before so you just gave me some ideas.Thanks

Posted: Sat Feb 14, 2009 11:42 pm
by inonickname
sputnick wrote:Inonickname, I think that was rather unfair, those are much different, apart from being smaller, and MEANT for pressure, they still have different applications and material thicknesses and materials period
I wasn't talking about deoderant cans....Second post..
Here..
Far out.. They were discussed in the thread? Unless I'm misunderstanding you..
Posted: Sun Feb 15, 2009 3:29 am
by Gippeto
The relief valve on those small propane tanks opens at 375psi.
To get more flow out of it, remove the plastic spacer, an o-ring, and the schrader core.
Then drill and tap for 1/4" npt.
Add a nipple, tee with threaded schrader, and a modded female QD, and you're half way there.

Posted: Sun Feb 15, 2009 4:03 am
by POLAND_SPUD
a word of warning... propane tanks are not designed to use air.... as air contains water some of it will condensate inside the tank causeing corrosion after some time...
so in other words your tank will gradually get weaker and weaker.. I've read about several things that can be done - you can:
- add a filter to limit amount of water getting into the tank
- add a valve for dumping condensated water ( and regularly dump some of it)
Posted: Sun Feb 15, 2009 4:06 am
by tape fist
ya that's easily solved by putting paint in it swishing it around and then pouring it out an letting it dry.
Posted: Sun Feb 15, 2009 4:42 am
by Brian the brain
I've got one that has 3/4" BSP threads on it.
There is no way I'll ever use it though.It looks too weak to be of any real use,
to me at least.
My guess is, it can take 100 psi safely, but that's about it.
100 psi was okay in 2005, but these days.....
Posted: Sun Feb 15, 2009 4:51 am
by tape fist
Brian the brain could you give me a picture of it please just want to make sure i don't have the same one.
Posted: Sun Feb 15, 2009 4:56 am
by Brian the brain
Ah, I completely missed page two.I was still referring to the drinking bottles.Sorry.
Posted: Sun Feb 15, 2009 5:01 am
by tape fist
oh its okay,i decided to move on to propane tanks after i got to talking with sputnick.