Toshiba MPF-2140 Spindle Bearing Failure
Possible cause of failure:
Rear roller bearing failed, inner race cracked & spun on the shaft, scoring the rear roller journal OD.
Rear hydraulic nut failed & came loose, OD rubbed out with bearing spacer. Oil inlet holes were stripped out from previous spindle rebuilder
Shaft tooling taper has acceptable runout but is very bumpy with poor tool contact.
Front housing ID is oversized +16/+18µ (ISO is +/-9µ) with score marks that have been previously stoned out.
Rear roller housing ID is -4/-10µ (egged 6 microns)
Front oil injector has damage from previous spindle rebuilder. Gripper fingers & TSC plunger have heavy wear.
OD of drawbar shaft is corroded & heavily scored from action of the springs.
Clean, inspect overall dimensions.
Grind, chrome plate & finish grind front housing ID, rear roller housing ID, rear roller journal OD & drawbar shaft OD.
Kiss grind shaft tooling taper. Repair damage to oil inlet holes, hydraulic nut OD & rear bearing spacer ID
Replace bearings, rear roller spring pin, GMN seal, o-rings, gasket, plastic oil lines, grippers & TSC plunger, rotary union, encoder sensor, assembly screws.