Atlas 6" Lathe Spindle Nut (1"x10 tpi)

I have always wanted to have a spindle nut for my Atlas 6" lathe that would protect the spindle threads when they are not being used. A lot of lathe owners make spindle nuts as an exercise in cutting internal threads. However, I wanted to see if I could accomplish the task with my Fabricator 3D printer and Design Spark Mechanical.

The threads were laid out using the thread formulas found at https://en.wikipedia.org/wiki/Unified_Thread_Standard .
The result of the print was a nut with good and tight threads. I added some oil to the threads the first time that I put the nut on the spindle. At first I had to use a 1-1/4" wrench to completely seat the nut on the spindle. Working the nut back and forth with the wrench, I was able to smooth things out to allow seating of the nut by hand. I am sure that printer related dimensional tolerances and random print artifacts caused the initial tightness.

The thread fit and quality of the nut was very good. Inspection initially and after I worked it on the spindle showed that the threads were in excellent shape without any shavings or other signs of damage. I am pleased with my new spindle nut.

I have included two versions, one that has a sleeve that covers the non-threaded portion of the spindle, and one that covers only the threaded part. The Design Spark Mechanical source files have also been uploaded.