Cleaning the dirty old grease out of the focus mechanism on the microscope base. Thankfully the BHM mechanism seems much simpler than the BHTU in Carl Hunsinger's videos.
Remove trim. Remove slide block. Remove ball bearings and bearing races. Clean off grease, re grease. A 50/50 acetone and isopropyl mix in a Gu pudding pot is great for getting the old grease off the BBs and stopping them from escaping.
#OlympusBHM #microscope #repair