Hi.
One of these sanders
----> **broken link removed**
is being used as a scrubber, with a gentle non abrasive pad.
Its motor is 120VAC, 2.6A. I suppose it is an universal type.
Now works with a 60W light bulb in series, brings the energetic vibration down to desired.
Any risks of damaging the motor ? When stalls, lamp gets brighter and all behaves fine so far.
A possible problem with using an incandescent lamp as a series resistor with a motor is that, as the motor is loaded and the current increases, the lamp resistance goes up, so the motor torque is less than if a normal power resistor were used for the same purpose. If that characteristic is okay for your use then using the lamp is fine.