Sasha D's Crayford-style focuser for the Hadley telescope is excellent! I highly, highly recommend it. Focus adjustments are MUCH smoother with the Crayford-style focuser.
I ended up stripping the plastic threads on one of the setscrews in the thumbwheel, so I decided to make a version of the thumbwheel that uses heat set m3x.5 threaded inserts to make it much easier to get a little torque on the set screw without worrying about stripping the plastic threads.
I also made the knobs a bit longer so that they stick out slightly past the edges of the main body of the focuser to make them a bit easier to grab.
The hole for the m3x.5 insert is 4.5mm in diameter and 6 mm deep. I ended up needing to clean out the hole that the adjustment rod inserts into with a 4mm drill bit after the heat set insert pushed a bit of plastic into the rod insertion hole.
The author remixed this model.