These images are from two very similar projects that I’ve just helped my friends with. They want to be able to hold bike frames on their alignment tables by the head tube. They both purchased used bench centers, and we had to make bull nose centers for them.
The fit up needed to be very close, so we were working to within a few tenths.
The other complication was that one of the centers on each set was spring loaded and utilized a rack and pinion to withdraw it… so we had to mill those rack gears.
