From the moment your spindle arrives in our facility it is assigned to a skilled, highly trained technician.  The technician assumes responsibility for the complete spindle rebuild from disassembly to final run-off.  This ensures the highest degree of ownership and craftsmanship and in the event you need additional after repair support, the technician that performed the repair will assist you with any additional issues.

  • Disassembly & Evaluation
  • Rebuild
  • Run-Off (Testing)


  The Disassembly and Evaluation

  1. Stator (on motorized spindles) is electrically tested for resistance and ground
  2. Spindle completely disassembled and cleaned
  3. Components measured, ie:
    1. Bearing journals for size and concentricity
    2. Bearing housings for size and concentricity
    3. Bearing shoulders for perpendicularity to bearing journal and to bearing housing
    4. Concentricity of rotor (on motorized spindles)
    5. Straightness of shaft


  1. Drawbar springs are evaluated
  2. Tool gripper fingers are evaluated
  3. Tool taper is inspected for contact surface and concentricity
  4. Face of taper is measured for perpendicularity
  5. Bearings evaluated for failure analysis
  6. Sensors are tested for operational function

Repair Quote Sent To Customer


  The Rebuild

  1. All components are thoroughly cleaned and all corrosion is removed
  2. Components requiring GPG (grind, plate, grind) will undergo this process as necessary
  3. Stator (motor) rewound if required
  4. Breeze grind of components as necessary to restore concentricity or perpendicularity
  5. Rotating components assembled and balanced as a system


  1. New O-rings installed
  2. Bearing spacers are ground to properly pre-load bearings
  3. New bearings are washed and properly greased (or cleaned for oil/air applications) prior to being installed.  We do not install bearings right out of the box.  They are dirty.
  4. Tool retention set
  5. Taper concentricity is adjusted
  6. Coolant system is pressure checked against leakage
  7. Spindle housing is painted to original color


  The Run-Off (Spindle Testing)

  1.  Spindle placed on test stand and gradually brought up to rated speed while monitoring and stabilizing bearing temperature
  2. Overall vibration, acceleration, displacement, and peak to peak vibration, is measured and documented


  1. Quality report issued and sent with spindle

This process is performed on each spindle.
Tolerances are within manufacturers specifications
ISO/ANSI G-0.4 Quality Grade is exceeded
All Bearings are grade ABEC 4-9 depending on application