Spindle Motor Repair

Every spindle motor that enters our shop goes through an in-depth refurbishment procedure. When you send your spindle motor to us, we go above and beyond to rebuild your motor back to like new condition.

Over the years, we’ve refined our spindle motor repair process to reflect our customers’ needs. Our goal is to refurbish spindle motors efficiently and effectively. When a motor enters our shop, we start with an extensive evaluation. The diagnostics from the initial evaluation shape the course of action our technicians take to refurbish the spindle motor. Through our spindle motor refurbishment process, we can restore our customers’ motor back to or exceeding factory specification.

Fanuc AC Spindle Motor A06B-1474-B128#F521

Spindle Motor Manufacturers We Repair

Allen Bradley(AB) Baldor Cincinnati Milacron
Fanuc Fischer Fuji
Getty’s GMN Haas
HSD Indramat Komo
Mitsubishi Moog Okuma
Perske PSD Colombo Siemens
SKF Yaskawa

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1. Spindle Motor Evaluation

During the evaluation stage, we inspect each component of the spindle motor to pinpoint the issue. Our technicians will examine the following:

  • Bearing fits and bearing journals on the rotor
  • Motor cooling jacket integrity (if applicable)
  • Flange fits and mounting surface imperfections
  • Broken conduit boxes
  • Worn output shafts, keyways, and pulleys
  • Winding condition
  • Cooling fan condition
  • Feedback sensor output
Servo Motor Repair Testing
The condition of this Mitsubishi spindle motor fan is how a fan typically arrives to our shop.

2. Spindle Motor Refurbishment

After the quote has been sent and a P.O. has been received, we begin our spindle motor refurbishment process. Any faulty or defective parts that don’t meet factory specification will receive the proper repairs or be replaced. Some of the standard procedures our technicians will complete include:

  • Wash & bake stator
  • Rewind Stator
  • Bore & bush bearing fits
  • Repair bearing journals
  • Balance rotor
  • Rebuild or replace cooling fan
Disassembled Fanuc Spindle Motor
Above is a Fanuc spindle motor completely disassembled. Parts that didn’t meet factory specification were replaced or received the necessary repairs.

3. Spindle Motor Assembly & Testing

After the necessary repairs have been made, our technicians will begin assembling and testing the spindle motor. While the motor is disassembled, we will test the individual components of the motor. Our technicians will perform the following preassembly test:

  • Megger and surge test stator
  • Winding resistance test with a Low Resistance Meter
  • Indicate all rotor Journals for TIR (Total Indicated Runout)

Once the preassembly testing is complete, our spindle motor technicians begin rebuilding the motor. During the assembly process, we use high-grade replacement parts. The quality of these parts are better than the original parts used in the motor and they help improve the life of the motor. Our assembled spindle motors include:

  • High speed bearings
  • High speed grease or oil
  • New seals, O-rings, and gaskets
  • New feedback sensor
  • Coolant couplings
Repair of Servo MotorSpindle Servo Motor Repair
We stock a variety of feedback sensors including this magnetic proximity sensor. Above is a reading of it’s output for a Fanuc spindle motor.

4. Spindle Motor Final Testing Procedure

Once the motor is reassembled, the spindle motor is final tested. Over the years, we’ve acquired a large assortment of spindle drives. Our final testing department runs every spindle motor on a factory specific drive at its maximum RPM.

  • Test feedback sensor output to ensure the signal amplitudes are up to factory specification.
  • Make sure currant loads are equal on each phase.
  • A final vibration analysis is also conducted to ensure the spindle motor will run smoothly when it is reinstalled in your machine.
Spindle Servo Motor RepairsSpindle Servo Motor Repair
Above is a spindle motor being run on a factory drive  and a vibration analysis report  that was performed simultaneously.