The Drifter will use GSO’s dual-speed Crayford focus knob upgrade kit as its focus knob. It’s a complicated assembly and worth using an off-the-shelf product that’s already battle tested. This is one of the few off-the-shelf components in the Drifter.
The first half of making a custom slot in the drive block for this knob is complete. It was tricky leaving enough material on the other side for the bearings. Of course, it must be aligned perfectly to the drive plate. The drive plate screws into the draw tube so that the proper tension can be fine tuned.
Part two will be building something simple on the other end to hold it in place.
At that point, the focuser will be ready for unit testing.