Mechanical STL Thread Repair

I have a nearly-finished mechanical part that’s ready for 3D printing, but the threaded sections are giving me trouble. Both the internal and external threads need to follow standard metric specifications so the piece mates cleanly with off-the-shelf hardware. Everything else in the model is already built—only the threads must be corrected and verified.

You’ll receive my working file along with the key dimensions and the mating parts I’m targeting. All I need back is:
• A clean, print-ready STL containing accurate metric internal and external threads.

If you generate your threads in SolidWorks, Fusion 360, Inventor, or another CAD tool, that’s fine—as long as the exported STL prints correctly without post-processing. I’ll run a quick test print to confirm fit; once the nuts and bolts turn smoothly, the job is complete.