Motor City Machine Tool specializes in GMN spindle repair for CNC machine tools such
as: HMCs, VMCs,  and Grinding Machines.  

We replace and in stall new: precision bearings, seals, o-rings, and all damaged components.
All components are tested:  Motor  winding, drawbars, encoders, and Vibration Analysis is
performed on all spindle bearings.

  • GMN & Other Spindle Repair Testing
  • All Spindles are test run to maximum rpm
  • Spindles are initially ran at 5% of maximum speed
  • Bearing Temp & vibration are checked.  Once verified to be with  OEM specs, the rpm is
         increased to 10% of max. rpm
  • All spindle units are checked before & during the increase of rpm at all intervals
  • Once they are proven to be within OEM specs they are increased by 10% intervals of the
         max rpm until max rpm is achieved
  • When max rpm is achieved the spindle is ran for 1-2 hours
  • Only when bearing temp & the vibration analysis readings are within spec is the unit
         approved for shipment

Testing Equipment
  • Run-in Procedure
  • Testing  Equipment
  • Grease packed spindles
  • Belt-Driven Spindles
  • Motorized Spindles
  • Oil Mist Lubricated Spindles
  • High Frequency Spindles (Up to 250,000 rpm)
  • Cartridge Spindles (Special Fixtures are built)
  • Pressure Checks to detect leaks
  • All drawbars checked with Pull Force Rention Guages
  • Photos on Test Stand
  • Spindle Repair Testing
  • Repair Services


Lead Times                                                                             Warranty
1-3 Days for Emergency Repair                                               All GMN Spindle Repairs have a
1-2 Weeks Standard Repair                                                      full 1 year warranty.
GMN Spindle Repair
Motor City Machine Tool Repair can rebuild any GMN VMC spindles, GMN HMC spindle, GMN grinding spindle, GMN
high frequency spindle, GMN motorized spindle etc....  We stock all necessary components to ensure the best possible
lead times.  
Sales@motorcityrepair.com

32535 Schoolcraft Rd
Livonia, MI 48150
(734) 261-8600  Office