Propane torch compression fitting?

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daberno123
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Wed Jul 30, 2008 2:17 pm

I'm starting to get the propane meter together for my upcoming combustion gun. I've heard that using a big pipe wrench you can take off the angled part of a propane torch and you can use a compression fitting to convert these threads from 1/4" compression to 1/4" NPT.

Is this what I need to do the job? I've never used compression fittings before.

McMaster Part #5272K191
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starman
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Wed Jul 30, 2008 2:26 pm

Yep, but you can get the same thing at Home Depot...in the Watts brass parts section. Also, you'll not use the compression ring and nut that comes with it.

Just be warned, that angled pipe is really glued in there well. Hold the valve part solidly in a nailed down vise while you torque on the pipe. The longer the pipe wrench and bigger the muscles the better... :wink:

You'll hear it snap when in breaks from its monsterous grip.
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daberno123
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Wed Jul 30, 2008 2:58 pm

Thanks starman I'll take a look next time I go to Home Depot.

As for the pipe wrench, I suppose the 24" one I recently bought will have to cut it :wink:
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DYI
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Wed Jul 30, 2008 8:35 pm

I usually just grip it in one pipe wrench and turn it with the other. For such a small fitting, it takes a hell of a lot of torque to remove (more than a 1/4" fitting turned near the point of breaking the fitting). Be warned, the threads aren't exactly the same as 1/4" compression, and you will need a generous dose of telfon to make up for the small difference. Certainly worth it though, and a lot cleaner than sawing off the bent brass piece.

A 24" pipe wrench will certainly do the job, as I know I've removed one with a 12" wrench before. Almost anyone has the power required to do it, it's more the fear of snapping the thin brass under so much strain that makes it difficult to do.
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starman
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Thu Jul 31, 2008 3:03 am

BTW, I forgot to credit DYI for illuminating this process to me to begin with. It SOOooo changed how I did the whole propane adapter thing.

Thanks again DYI!
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