Okamoto OH-20M Seized Grinding Spindle
Possible cause of failure:
Spindle was seized incoming. Right rear corner of dovetail mount is chipped.
Coolant contamination caused corrosion of spindle interior and failure of front & rear bearings.
Rear bearing cage was destroyed & the debris caused the rear labyrinth spacer to rub out on the rear cover.
Tooling pilot ID is oversized and has 30µ runout, pilot face has 15µ runout.
Drive pulley is worn & damaged, pulley taper has 9µ runout.
Clean, inspect overall dimensions.
Repair rubout damage to rear labyrinth spacer.
Grind, chrome plate & finish grind tooling pilot ID, kiss grind pilot face & pulley taper.
Replace bearings, drive pulley, o-rings & assembly screws.
Adjust preload, balance, assemble and break in. Final quality control inspection.