Tech Torqs #6: Slotted vs Slotless Motors - What’s the Difference?

Not all motors are built the same - and the difference between slotted and slotless stators has a big impact on performance.

Slotted motors use metal teeth in the stator to guide the windings and concentrate the magnetic field. This improves torque density but introduces cogging torque, which can cause vibration and noise, especially at low speeds.

Slotless motors, in contrast, eliminate these teeth. The windings are laid inside a smooth cylindrical stator, often self-supporting, which drastically reduces cogging torque, resulting in smoother, quieter motion.

The trade-off? Slotless motors usually have lower torque density.
Unless they use straight windings and a high copper fill factor, like in our SlimTorq™ motors.

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If you have a question about motors or motion systems, share it in the comments on our LinkedIn post or send it to us directly - we might feature it in the next Tech Torqs episode.