Old tub fixture + handheld shower head?

SteamFTW

First, I have to state the obvious: this site is fantastic. What started as my first-stop for steam is now my first-stop, period. I never come away without learning something, even if that "something" is a rare (but really annoying) gotcha to be on the lookout for. A big thank you to everyone who shares their experience.

This is from the latest edition of "Oh, [son-in-law], while you're visiting, can you....?"



[Edit: When I wrote this, I had not yet removed the nipple and verify the thread type of the fixture outlet. In fact, at the time of this edit, I still have not done that. I will not be back at this location until tomorrow. So... if my assumption about NPTF (in the fixture outlet) is incorrect, I apologize heartily.]

Correct me if I'm wrong, but those handheld shower things have NPS ("straight-thread") connections, right? Even things like this Delta-U4929-PK-3-Way-Shower-Arm-Diverter require that I have NPS at the water source to connect to, because they're meant to connect to a shower arm. But there's NPT (tapered) at the old fixture. How would you get from NPTF (out of the fixture) to NPSF (into the shower hose), with a good seal? (i.e not as I found it with loads of tape/wick and hoping you tighten the plastic NPSF threaded end enough to seal without cracking it).

Ideally, I'll put a 3-way ball valve (and move the "tub" outlet higher) so that the tub can still be filled at a reasonable rate, rather than wait for the shower head spray to fill it. But I need to solve the NPT x NPS connection first.

I came across what claimed to be a 1/2" NPS x 1/2" NPT hex brass nipple, but my concern would be that the tip of the NPSM end would cut up the gasket in the flex hose NPSF end. Probably nothing that a little time with a grinder wouldn't take care of, but I didn't know I'd need my workshop on this visit.

What say ye?

Happy New Year's Eve!

mattmia2

It should be npt to npt, shower arms are npt but consumer diy products do all sorts of weird things like try to make them bottom and seal on a washer instead of sealing in the threads. wick/setting type dope/rtv can probably get it to seal up.

If you get the connections above the drip line and the shower head has a vacuum breaker or at least a check valve you at least somewhat solve the cross connection issue.

Jamie Hall

Watch out. Not only may the thread be a different -- or non-existent -- taper, but you have no guarantee that the thread ptich (threads per inch) on the old faucet is the same as on a current fitting. Don't ask how i know...

mattmia2

There are very nice faucets with a gooseneck spout above the drip line and shower head connection that you could replace that faucet with that would solve all your problems and not look like someone was doing what they could with what they had on their truck.