Backing off?

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YossiD

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When assembling plumbing fittings, frequently alignment is important, such as when assembling a tee fitting. Sometimes it feels like I can tighten one more turn in order to get the correct alignment, and then find that I can't. When that happens is I have to back off a bit to get the correct alignment. If using teflon tape or pipe dope will backing off compromise the sealing? Would it be better to start over with new dope or sealant, and possibly some wicking?

Thanks
 

Helper Dave

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If you're backing off a slight bit to get level, or aligned, you're probably okay. Any significant amount, you should just start over.

Getting to the point you can't tighten it any more usually means you're well beyond how tight you need to be anyway. Especially with brass fittings, you can start to deform the threads if your Herculean strength goes overboard. Lol
 

frodo

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ALL 1/8" through 2" fittings have EXACTLY 7 threads.

ALL 1/8" through 2" fittings require 7 turns for full contact.

In our imperfect world 5 through 8 total turns is 'acceptable'.

3-5 turns by hand then 2-3 turns by wrench = 5-8 turns total
 

YossiD

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Thanks for the replies. This pretty much confirms what I usually do.

Some times the fitting doesn't feel terribly tight when the alignment is right, and I can manage ~3/4 of another turn before it feels like I might do some damage by applying Herculean strength. when that happens I generally start over with more thickness of teflon (though I don't really like doing that) or some wicking so that the fitting will be more snug when it gets to the proper alignment.

Nice to have validation for my common sense approach.

Never knew that all 1/8" through 2" fittings have exactly 7 threads (maybe it'll come up in a trivia quiz one day). Live and learn. Is that true for straight threads (NPS) as well as tapered (NPT)?
 
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