Repair threads on pipe fitting?

[aangel]

I have a 90 degree orifice fitting for one of my banjo burners. Its first thread seems to be galled or smushed or something. In any case, I can't thread it onto my burner. How do I fix this? Is it possible to recut brass threads?

 

[IslandLizard]

Brass doesn't gall, IIRC, but threads are easily damaged because the metal is soft. Just rethread/true those first turns. Do use teflon tape and be careful when threading it on again.

 

[aangel]

How do I rethread / "true" those threads? (Seriously don't know anything)

 

[IslandLizard]

Ideally you would need a die of the right size/pitch. If it's only the first turn of the thread that's damaged you could file it down a little until it grips. The burner is cast iron, so it will effectively "re-thread" your brass fitting. So make sure the iron threads are clean and not damaged or filled with rust. A little oil helps to reduce friction.

 

[aangel]

So I managed to solve this. Switched to pipe dope from tape and put a bunch of pressure into the fitting as I twisted it on. Hurrah it worked! Scary thing: I had to remove the fitting and put an air guard on, and the cast iron had carved noodles of thin brass out of the orifice.

 

[IslandLizard]

I'm glad it worked out after all and your brass fitting didn't snap off. Pipe dope is a great lubricant, I'm surprised you have that around.

I forgot to say, sometimes chasing the cast iron threads with a well lubricated tap works wonders too.