Tub faucet pipe too long

Question

I'm trying to replace my tub faucet because the old one sat about 1/8" away from the wall and felt loose. As it turns out this is most likely because the pipe coming out of the wall is 1/8" too long. It's a 3/4" pipe threaded at the end and it seems like most faucets using this connection require that pipe to be exactly 4" out of the wall (or probably slightly less to be honest) but this pipe is 4-1/8".

I want the new faucet to fit snuggly against the wall but it has the same issue as the old one, fully threaded on it's still about 1/8" away from the wall. I do have a pipe cutter but I don't think it would work very well on the threaded section of the pipe, however I was thinking if I just extend the threads on this pipe another 1/8-1/4" I should be able to thread the faucet on further because the female threaded section of the faucet looks significantly longer than the male threaded section of the pipe.

Is that a bad idea, and should I just cut the pipe somehow to be the correct length? Also if I do end up needing to cut the pipe is there a correct way to cut cleanly through the threaded area?

Answer 1

pipe threads are tapered so cutting the pipe shorter (eg use a hacksaw) would likely not result in the faucet going on any further, instead you'll probably need to have the threads on the pipe re-cut deeper and longer.

Answer 2

1. there are many brands and types of tub spouts and there is no standard for pipe length out from the wall.
2. you cannot just cut that type of pipe. It has a tapered thread, so cutting a bit of the threaded portion off will ruin it unless you have a pipe threader to re-thread it.
3. a 1/8" gap is not unusual at all (and is not necessarily a bad thing, see detail below) and would normally just be sealed with caulking.

In your original problem: "tub spout... sat about 1/8" away from the wall and felt loose" the only real issue is the second part, the fact that it was loose.

Detail- because pipe threads are tapered and rely on that taper to effect a proper seal, using a shorter pipe presents the possibility that the spout will strike the wall before the spout is threaded fully on. Most plumbers would rather caulk a small gap and know that the spout is threaded fully on with no leaks, than thread the spout tight to the wall and not be sure the thread is fully seated.