I am planning to install a shower wall outlet with an adjustable slide bar next to it to rest the hand shower, but I am a bit confused on how to set up the nipple that bridges the drop ear 90 behind the wall and the female wall outlet.

This is a picture of such an elbow.



The installation calls for the nipple to protrude 5/16" from the finished wall.



So, if the "front" of the drop ear elbow is 1" back from the finish wall, and the nipple needs to be 5/16" out of the wall, assuming the nipple will thread 1/2" into the drop ear elbow, the exact total length of the nipple I need is 1/2" + 1" + 5/16" = 1-13/16", but I won't be able to get a nipple of that exact length, so I'll end up using a 2" nipple right?

The second question is, how do I thread the nipple in? Hand thread until it won't turn anymore then what? I can't put a plier or wrench on it or the threads will be damaged, so the only thing I can use to thread it in is this short snd stubby wall outlet itself? If so if I need to take it apart and turn it counterclockwise, whether it unthreads at the drop elbow or at the outlet, I will have to destroy the threads to uncouple the nipple right?

There has to be a trick I am missing right?

You can custom make nipples by soldering 1/2 in MPT Copper adapters on to the ends of a short piece of 1/2 in copper pipe. You might end up having to make two or three before you end up with the exact length needed. The hex shoulders will enable application of a wrench to tighten the nipple into the drop ear.

Nipples without shoulders can be tightened or loosened with inside wrenches.

I think the distance I need between the drop ear and the new fitting is such that it's shorter than two copper male adapter back to back. I'll double check again.

I have these internal wrenches, I have not used them for nipples.

I seem to remember having seen nipples where the inside of the nipple is a hex shape that you can put a male hex fitting inside it to crank it tight. I don't know whether I am just imagining it or this exists...

OK edited to add, I just saw this by Googling. This is a wall elbow where the male connection to the shower hose is a threaded end with a hex internal shape. I assume this is to help with fabrication and assembly.



Are standard nipples available with this hex shape so a hex tool (like a larger allen key) can be used for tightening?



Edited 1 times.

Don't know about hex drive nipples.

Street adapters are available. Street into spigot might give you the right length.