M39 Lens to M42 Camera/Enlarger adaptor

A remix of a remix :)
Thanks to everyone involved before me:

- Aeropic, for the original M39 thread.
- Numanair, for testing and resizing the M39 thread (remix from Aeropic).
- Murin, for the M42 thread mount.

I needed an M39 to M42 adapter for an enlarger lens so i chopped together multiple files and also made some adjustments. I've trimmed it and made a conical taper so i won't need supports when printing.

As you see, i've tested it and it works with an M39 Voigtlander lens and an