View Full Version : Cutting a brass nipple
10-24-2005, 11:01 AM
Well I'm almost done with my bathroom remodel (10 months later :( ) and I have one problem with a separate handheld supply line in the shower. We are installing a separate shower head and handheld. Everything is tiled and when I set the ell for the handheld I based it on the overall thickness of the backer board, thinset and tile etc. to calculate the setback. Well it looks like I'm shy by about 1/16 - 1/8". When I put a 3" nipple in I have about 1/4" on the outside of the wall to mount the handheld fitting. Kohler suggests 9/16" but I think that may be too much. I think I need use a 3 1/8" nipple.
I checked with Ferguson today and they don't cut/rethread pipe that short. So I was thinking I could take a 3 1/2" nipple and cut it down and rethread it with a 1/2" NPT die.
The other option is to cut a hole in the wall behind the shower and try to reset the ell.
Any advice on how to solve this problem?
10-24-2005, 11:19 AM
Don't know why 3/8" is that critical if your using a brass nipple.
How are you going to hold the nipple to re-thread it?
There is no guarantee that you will have the same depth cut if you use a new die.
10-24-2005, 11:35 AM
I'm not sure what you mean
"Don't know why 3/8" is that critical if your using a brass nipple."
I was going to screw the die on first and cut both ends and then use the die to clean up the threads when I unscrew it.
I was planning on holding it with vise grips and then clam the vise grips.
Any other suggestions?
10-24-2005, 11:43 AM
I just guessed that you were using a chrome, brass nipple.....
Why so critical about the length of the nipple. Of course, I may not understand what your doing either.
10-24-2005, 11:49 AM
It is a regular brass nipple. Currently a 3" nipple screwed into the ell with teflon tape etc. extends beyond the tile wall by about 1/4" to 3/8". Even though Kohler recommends a 9/16" extension from the wall I think that will be too much.
What I was trying to do is to get the nipple to extend about 1/2" from the wall so that when I mount the fixture I don't screw down on the tile and crack the tile. The fixture has a estceon (spelling?) that will cover up the tile and hole.
Sorry I'm not being clear.
10-24-2005, 12:33 PM
Again, why can't you let that nipple be 1/4" to 3/8" longer? Is it because of cosmetics or is it a spec. that you have to meet.
This sounds unusual to me.
What happens if it is a smidgen longer?
10-24-2005, 12:36 PM
I would try trimming the 3 1/2" nipple and see how it goes. I expect that you should be able to just cut a bit off and then rework the threads. Even if it takes you a few tries, you should be able to do it.
10-24-2005, 12:46 PM
Here is the elbow that I'm installing....
Basically if I go with a 3 1/2" the elbow will stick out too far from the wall. The escutcheon will not cover up that large of a gap.
Flannigan - I'll give it a shot.
10-24-2005, 01:18 PM
Thanks for the pic.
10-24-2005, 02:33 PM
Instead of teflon tape, try pipe dope. It will thread deeper. If you're still sticking out too much, try using a 4in1 screw driver less the bit shoved inside the outlet of the elbow to make one more 360° turn, making sure not to damage the finish or the threads on the elbow. If you must cut a brass nipple, take the nipple you wish to cut, put tape on one end and screw it into a gal coupling attached to a 6" gal nipple at the other end, clamp the longer nipple with the jaws of a threader, then cut and thread the brass nipple. Afterwards, unscrew the brass nipple from the coupling and away you go. If that still doesn't work, you can always buy a nipple chuck, which are available for most freestanding electric threaders.
10-24-2005, 05:00 PM
When I got home tonight I remeasured things. The depth of the ell in the wall from the outside of the tile to the ell is 2 3/8". When I thread the brass nipple into the elbow hand tight it is 1/4". When I hand tread the nipple into another ell it comes to 1/4". So it looks like the total distance is 2 7/8" which should leave me 1/8" to work with. I guess I'll try fitting the 3" nipple again to see where things actually come to.
Thanks again for everyones help.
SRDenny - If I do need to cut and rethread, are you talking about using an electric threading machine? I would have thought Ferguson's whoul dhave suggested that. Oh well.....
10-24-2005, 05:06 PM
Pipe threads are tapered, so you can't do like you would with a machine screw and thread the die on, then back it out over the cut.
A good shop, but not necessarily a supply house, would have a nipple jig for their pipe threader. You may have to talk someone into doing one for you.
10-25-2005, 06:30 AM
Guys you've been a great help.
One last question... Can I expect to get the threads in 1/2" for the elbow and the ell? If I can without torquing the ell off then I think I might be able to use a standard 3 1/2" nipple.
10-25-2005, 07:59 AM
Can't you just solder a 1/2" male threaded adapter to both ends of a short piece of 1/2" copper to get any length you need? I've done this several times since I don't have a thread machine and sometime need a non-standard length nipple. :)