I think it would be very helpful for all of us who have printed this, and had the knob twist off, if you could make a hexagonal bore,
clear through the threaded part, so we could put an allen wrench in there, to break this part loose. I made a second one, thinking
that if I corrected the drawing to print a higher density, it would hold up to breaking loose, but it also twisted off.
If I knew how to work with .STL drawings, I would show you what I mean.
This is one of the best things I have seen on here, all the same! Thanks.