Mazak H-400N Spindle Repair

This Mazak H-400N spindle repair runs at 10K RPM and has Cat 40 tooling. The customer needed their spindle rebuilt and the thermistor wires needed to be replaced. In these photos, the extended thermistor is pictured after it has been replaced. The spindle itself is mid way through the spindle repair and rebuild process.
Mazak VTC-16 Spindle Repair
7,000 RPM
This customer wanted a ballpark quote for his spindle repair. He was satisfied with the amount so he sent his spindle in to be thoroughly quoted, which is always a free service. After he received the actual quote he decided to proceed with the repair.
We cleaned and inspected the overall dimensions of the spindle. We discovered that the cause of failure was due to contamination. The taper had 40 microns of runout. The tooling rocked in the taper and the bellevilles were worn.
We replaced the bearings. We also ground, chrome plated and reground the taper. The preload was adjusted. The spindle was balanced, assembled, broke in. It was then checked by our QC department and shipped back to the customer.
Mazak
CNC-9
4,000 rpm
Due to economic times this customer was going to rebuild this Mazak CNC-9 spindle themselves. They disassembled the spindle and found that when the spindle seized up the bearings spun on the shaft causing damage. They decided to send the spindle in because they were not equipped to repair the shaft. The shaft is a very critical part of the spindle and if it is out of tolerance putting new bearings back on the shaft will not make the spindle life last any longer. Each part must be at or within the ISO tolerances allowed. This customer made the smart choice and is now up and running with a spindle that is at OEM specifications.
Mazak QT6 Rush Spindle Repair
7,000 rpm
We received this spindle from our customer late morning on Wednesday. It was broken down and evaluated by mid afternoon on Wednesday. We spoke to our customer about the repair, what was needed and the options they had. The spindle was approved late Wednesday.
By Thursday morning the spindle had been completely cleaned and ready for assembly in our clean room. By late Thursday afternoon the spindle was assembled and running on one of our test stands.
Our customer picked up the spindle early Friday morning and their Mazak machine was making parts by days end.
This was the first spindle we had done for this customer and the repair was treated with the urgency required for the situation. If you are in need of fast turnaround times on a spindle rebuild please call one of our staff to discuss the repair. We will always do everything possible to get you up and running.

- Mazak H630
Mazak H630
This spindle was exchanged with the OEM the last time it failed. Our customer came to us because it failed prematurely and the OEM would not cover the repair under warranty.
When we received the spindle and evaluated it we determined that when the spindle was exchanged the new spindle they installed had air purge capabilities. Their machine did not have this option and the OEM did not plug the air input hole. This gave coolant a direct path to the bearings and led to the spindle failure. We placed a removable plug in the air purge and gave instructions to our customer for the installation of an air purge system.

Mazak 10800 BIG PLUS PLUS
Mazak 10800 BIG PLUS PLUS
BIG PLUS 50 taper had run out and only 25% contact. Rear housing out of ISO spec.
- We ground plate ground the taper to BIG PLUS specifications and ground plate ground the rear housing. We were able to get 95% taper contact and 95% face contact. Final QC with certified BIG PLUS tooling showed less than 3 microns run out at the end of a 12″ test bar that repeated for over 20 tool changes.








