Having a printer is awesome. I was shopping around for knobs since it seems all the ones I have are too small or too big. Then I realized, I could just find a design and print it.
First one printed nicely, but I generated a support structure to stop the ball from potentially collapsing, but it generated supports in the center threaded portion which was almost impossible to remove. The second one I didn’t and it has a bit of a collapse on a small section, but perfect threads elsewhere.
Takes about 4 hours to print, but no effort on my part, maybe 5 mins or so of setup. Filament used I think is something pretty insignificant.