When a spindle loses power, trips its drive, or runs hot for no mechanical reason anyone can find, the motor moves to the top of the suspect list. The way to settle it is the way our inspection settles everything else: test it and let the measurement decide.
Winding testing is part of the inspection
Motor winding testing is a standing step in the MZI inspection room, alongside encoder and proximity switch testing. On a motorized spindle, the one with the motor built into the cartridge, that is unavoidable: the rebuild involves the motor by definition, and the windings get tested with the same rigor as the bearing journals get measured. On externally driven spindles, testing the associated motor answers the question every shop asks when a spindle misbehaves, which is whether the problem is mechanical, electrical, or both. The servo motor, spindle motor and gearbox pillar covers how the pieces fit together.
What rewinding restores
Motor rewinding is one of MZI’s listed services. When testing shows the windings have failed, rewinding rebuilds the motor’s windings rather than scrapping the motor, which matters most on motorized spindles, where the motor and the spindle are one unit and replacing one means replacing both. The same discipline as the mechanical side applies: find what failed, document it against the serial number, quote the correction, and proceed on your purchase order.
When the motor fails alongside the spindle
The events that take down bearings do not always stop at the bearings. Contamination and the heat of a failing spindle put the motor under stress too, which is why a spindle that came in for bearing noise still gets its windings tested before the quotation is written. It costs you nothing to know: the disassembly, inspection, and line-item quote carry no charge until a purchase order approves the rebuild.
MZI also repairs electric motors beyond the spindle itself; that capability is covered on the electric motor repair page. For feedback devices, the sensors that tell the control what the motor is doing, see the encoder and proximity switch guide.
Start with a phone call
Edward Zitney
President
(714) 475-4016
He has spent more than 44 years in spindle rebuilding and remanufacturing. He learned the trade over more than two decades at Precision Balancing & Analyzing, the shop long regarded in the industry as the standard for spindle work, later oversaw SKF Machine Tool Services, held service leadership roles at Setco, and wrote a published column on spindle remanufacturing for Fabricating & Metalworking.
Marco Guerrero
Partner
(949) 374-0060
He came up on the shop side of this industry. He started with his hands, welding and fabricating for the racing industry, then spent fifteen years as general manager growing a machining job shop, the same kind of shop that sends MZI spindles today. He has sold CNC machines too, so he knows what new equipment costs and when a rebuild is the smarter call. Today he and Ed are partners in MZI Precision, and his standard is simple: every customer feels informed and supported from the first call to the day the spindle ships back.
Call (714) 379-6505 and describe what changed. With a little information about your spindle we can diagnose the problem and determine your best action.
What to expect on the call:
- You talk directly with a spindle expert.
- Some problems can be diagnosed over the phone, and a few do not require removing the spindle at all.
- If your spindle should come in: disassembly, inspection, failure analysis, and a line-item quote, at no charge until your purchase order approves the rebuild.