24/03/2026
Servo motors fail in ways that aren't always obvious. Bearings are the most common culprit β they wear gradually, and the consequences follow a familiar path: rising vibration, drifting positional accuracy, heat building in the winding, and eventually a hard failure. But replacing them correctly means precise tolerance measurements, the right bearing preload, and proper rotor balancing after assembly. Shortcut any of those steps and you're not fixing the motor, you're delaying the next failure.
Then there's the encoder. If it drifts just 3-5 mechanical degrees from its factory-set position, the motor either won't run or loses torque dramatically. This makes encoder calibration mandatory as a standard part of every service.
The rotor magnets are where things get more complicated. In synchronous servo motors, weakened or partially demagnetised magnets cause problems that are easy to misattribute β reduced torque, irregular response, a drive working harder than it should. Finding the real cause means mapping the magnetic field across the full rotor surface. While most workshops tend to write off the motor at this point, we developed a reliable array of solutions, including re-magnetising existing magnets, manufacturing new ones, or rebuilding the rotor entirely from scratch if needed.
One thing that often gets overlooked is the gearbox. In many applications β robotic joints, positioning systems, automated lines β the servo motor arrives paired with one. Servicing a gearbox properly requires precise knowledge of gear tolerances, bearing preloads, and correct lubrication. Get any of those wrong and the gearbox puts stress back onto the motor in ways that aren't immediately obvious, but show up in shortened service life and degraded accuracy. It makes far more sense to treat the motor and gearbox as one job on one system, rather than two separate tasks.
Done properly, a fully serviced servo motor should perform to OEM specification (or better) β reliably and for the long term.
This is why we cover the full scope: encoder calibration, bearing replacement, winding impregnation, rotor balancing, magnetic field mapping, gearbox servicing, and complete rotor rebuilds. If you're dealing with a servo motor issue or want to discuss a preventive servicing programme, feel free to reach out.
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