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

thingiverse

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. Print Settings Printer: Fabrikator Rafts: No Supports: No Resolution: 0.2 mm Infill: 50% Notes: Sliced using Kisslicer. Material is PLA. How I Designed This Thread layout dimensions: H = 0.866 (pitch) = 0.866 (0.1") = 0.0866 Dmaj = 1" = 25.4 mm Dmin = 1" - 2 (5/8)(H) = 0.89175" = 22.65 mm Top of thread V = Dmaj + H/8 = 25.676 mm Bottom of thread V = Dmin - H/4 = 0.8701" = 22.1 mm See spindle_nut_1x10tpi-2D.rsdoc for 2D layout of part. When the model was taken to 3D view, the thread profile face was rotated 90 deg using the Move tool and moved into the nut fully. The thread profile face was then pulled using the revolve helix and RH options.