Loose threaded joint

[Hazel]

I am installing a hand shower wall fitting onto a brass nipple. The fit between the threads seems sorta loose and I'm concerned that just using pipe dope or teflon tape wont seal between the threads. I wont know right away because any leak will be behind the wall. Is there a trick to ensuring a seal between loose threads?

Thanks,
Hazel

[markts30]

If the joint will not make up tight with the length nipple you have, remove it and use one 1/2" longer....
Tef tape and dope are not for making loose joints tight...

[Hazel]

I just don't trust that even bottomed out and tight that water wouldn't leak past if the threads were so loose

[GrumpyPlumber]

If there's any play in the fitting once you've hand tightened it then something isn't right.
You'll want to read the MFG info and be sure the threads are "1/2" IPS" or "1/2" NPT" threads.
If you're unsure...use both dope and Teflon...put the tape on in the same direction the fitting spins tight so the tape doesn't roll off as you tighten it.

[Hazel]

I saw an episode of "Ask this old house" where the plumber used what looked like string in the threads and pipe dope to connect an old radiator which had a sloppy fit

[jadnashua]

There are tapered threads and straight threads. If the threads on the fittings you have are BOTH tapered threads, it will get tighter as you screw it in and unless one is defective, you should not be able to bottom it out in the fitting. But, if one or the other is a straight thread, it will never seal with pipe dope and teflon (at least not reliably). That type of fitting, like a hose, needs a gasket to allow it to seal.

[leejosepho]

I just don't trust that even bottomed out and tight that water wouldn't leak past if the threads were so loose

Like one of the scenarios Jim mentioned, my guess is that the end of the hand-held has straight threads and an integral washer or seal of some kind. If that is the case, it should "bottom out" and there is no need for tape or pipe dope or for being concerned about the threads seeming to be loose in comparison to having tapered threads on both pieces unless the end of the nipple is badly formed or deformed.