With over three decades of industrial experience, Renown Electric is more than capable of providing clients with first-rate turning and undercutting field services.


Turning and undercutting of Electric Motors & Generators commutators are performed for various reasons, but most notably for preventative maintenance. For example: these services promote the uniform wear of motor or generator carbon brushes, which will extend the brush life.

Undercuts are essentially slits in the insulation found between the commutator’s segments; this insulation can be composed of materials such as mica, micarta, resin, paper, molding, and others. Separation of these segments is important because insulation can rub up against carbon brushes, causing them to wear very quickly. Over the service life of a DC motor, its commutator should be undercut to eliminate issues such as arcing, vibration, and excessive wear.

Turning is used to make a commutator’s brush track surface more concentric in relation to the shaft of the armature. The brush track surface needs a prearranged finish and concentricity—these attributes are obtained using our state-of-the-art turning equipment.

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Advantages of our turning and undercutting services include minimizing burrs swiftly and efficiently while providing the workpiece with the most ideal chamfer possible. We also test each commutator rigorously before the motor is used again.

At Renown Electric, we understand the significance of proper commutation and electric current transfer; these are two of the most crucial factors for ensuring optimal performance and long service lives of DC motors.

If your commutator needs maintenance, you can always contact us—our services are available 24 hours a day, 7 days a week.