Help! Need odd size brass nipples.

I've got to cut down three brass nipples to odd lengths to finish off my shower (3-1/4" and two @ 2-5/8"). These are 1/2" pipe. Is there an inexpensive threading die tool that I can buy for this application?

I called a plumber, but their threading tool won't handle short stock (no surprise). How does a plumber handle this sort of problem? You can't set the elbow to the correct depth in the wall because you have no idea how thick the mortar and tile are going to be. The trim (two body jets and one handshower outlet) need nipples of almost the exact length in order to seal against the shower wall.

Rick

A suggestion

They sell brass nipples at supply houses that are already threaded in various sizes, they should have them in stock.

Does it have to be brass nipples? Can you build to length needed using two male adapters and a short length of copper?

I'm going to look at how large the hole would have to be in order to use the male adapters. I'm loath to make the holes much larger. Right now I've got a tight fit around the brass nipples. I may not have a choice, however.

Rick

thread

You need a "nipple chuck" and a theading machine, not a hand die, to thread them. I could make the chuck, but the machine has to be a shop floor model, such as Home Depot has in their plumbing department.