Need an odd size pipe nipple

After months of tiling I'm back with a plumbing question. Say, for the sake of argument, I was an idiot when I mounted the drop ear for my hand shower, thinking that I could get a nipple to connect the drop ear to the trim piece (Moen) in any old size. Post tile, it looks that 3 3/4" is what I need. I tried a 4". The trim stands 1/4" proud when hand tightened. Found a 3 1/2" at a plumbing store. I get about 3 threads in each end (fully hand tightened is about 5 threads). With pipe dope and thread tape, will that be sufficient to prevent leaks? There will be some pressure in the line when I have the hand shower on, due to the limiter.

I know moving the drop ear would be best, but I'm trying to avoid starting another remodel by knocking out a wall in the other bathroom behind this shower. Any advice?

Wendy

I had a similar challenge last week and made my "custom" nipple with a piece of copper pipe and two male adapters. Probably not the way the real plumbers would do it, but it worked for my situation.

That was my first thought, but that mess probably won't fit through my kerdi pipe thingy. I'll check my adaptors while I wait for a miracle answer.

Use a brass pipe nipple, which can be cut and threaded to any length needed.

Phone around to some of the supply houses in your city, and if you are in luck and talk to someone very nice, they may fabricate a custom sized nipple for you. Be sure to use brass.

Thanks for the advice, Stormrider. I stopped by ******* on the way home from work and the hex parts on the thread adapters aren't any bigger than the barrel on the brass pipe nipples. A homemade nipple will work just fine. Whew! I'd go all fancy if I were a plumber with my own thread cutter, but I'm not to that level (yet).

A 4" might be your best bet when tightened. I did send you a PM.

You may even find a local outfit to chromeplate that brass nipple for ya-there's one around here that charges about $10 for a really nice polishing and chrome plating job.

a short piece of copper tubing soldered to male adapters on each end may be foolish. If the nipple needs to be removed years later, and the threads 'weld' 'corrode' themselves to the female threads of the drop earred ell, the copper tubing nipple may not withstand the torque and simply twist in two. If a short nipple is used on each end of a brass coupling, you have more threads to reach the right length according to rotations. If the nipple needs to be removed later and it unscrews further in the wall at the coupling, an EZ out will work on the pipe interior thread. However, I have found that some 3 1/2" nipples are shorter and longer than other 3 1/2" nipples. I would opt for the longest 3 1/2" nipple and double up on the teflon tape. To test, cap the stubbed out line or brass nipple and turn on the shower valve. If it holds full pressure, it will hold shower flow water pressure. Use a flashlight to look at the threads inside the wall cavity.

Get some pipe dies like these. You can find them at garage sales, flea markets and the auction site. They are very handy because they are flat. You can easily have room to put a pipe wrench on the pipe for a backup and thread the pipe with a channel lock pliers or a big crescent wrench.