When we moved – four years ago – one of the knobs on my classic floor model radio was lost.
Time to fix it. Usually the way to do this is with a resin casting, but I don’t have the materials for that, and a hundred dollar investment in all the stuff I would need seems a bit excessive for one knob.
So, we’ll go the 3D printing route. First design in Fusion 350
I scaled a couple of photos, and then traced a spline which I rotated around the central axis. Then I modeled the “pips” the same way, with a partial rotation and circular repeat.
Well, not quite. There were a couple of things I did not like. The most important was that the set screw was not holding well because I printed the knob with 20% infill, and the screw only had a couple of threads to grab. So I reprinted it solid and added a flat bottom at the same time – and now it’s really done.