Hardinge Lathe LC-1220
Our customer sent us this Hardinge spindle repair because it started to make noise and they knew failure was not far away. We disassembled the spindle and found contamination in the bearings from normal usage. We also found that the collet locating surface had 5 microns run out, the face had 4 microns run out and the od had 5 microns of run out. The front and rear nuts had been damaged and needed repair. We also manufactured a new spacer for the pulley. All the parts were cleaned and the spindle was assembled in our clean room.
During the final test run the spindle was out of our allowable tolerance for balance. We requested a draw tube and collet from our customer so that we could balance the entire assembly as a unit. Once the spindle was run with the additional parts only a small amount of trim balancing was necessary.
Hardinge C42 Spindle Repair
The bearings in this spindle reached the end of their lifespan. The ID collet taper had 10 microns of run out. We were able to kiss grind the ID taper and after assembly it had less than 2 microns run out. The spindle was rebuilt in our clean room and test run at 5000 rpm. When our customer installs the spindle they should be able to run a short warm up procedure and then they will be ready to make parts.
Hardinge T42 Spindle Rebuild
Grease lubrication, 5000 rpm
This spindle needed rebuilding because metal objects were caught between the back of the front flange and the front cover of the spindle. This caused damage to the front cover. We discussed the damage and the repair options with our customer and concluded that due to time and expense reworking the damaged cover was a better option for them than manufacturing new.
The rework of the front cover was completed in our machining department and the spindle was rebuilt in our clean room.