TL;DR: It’s on thingiverse
Been wanting a practical compass for a while. Criteria: quick to adjust, doesn’t move when set, light enough for drafting, rigid enough for scribing trim. I never could find a good one to buy, so I designed one.
If you want to carry it in a pocket, you can just tap the wedge out and flip the point so it doesn’t spear anything important:
I made a quick little fixture for grinding flats on the screws:
If you would like to print yourself one, you just need a flat-head M5 x 30mm screw, or #10 X 1.25”, with corresponding nut and washer. File/grind two flats on the head so it measures 6.5-7mm flat-to-flat. The model files are here. The compass is easier to use if you smooth the conical mating faces with sandpaper and scribble some graphite on them.
Email me if you want me to send you one.