In this video on GreatScott!, Scott asks the experimental question: Can you 3D print a working DC motor? He then talks us through the components of a DC motor, how he designed and 3D printed one, and shows how he was able to get his motor working (just add bearings and winding coils!).
But the resulting motor had rather unsatisfying torque. He constructs an experimental apparatus to try and get some performance stats, but the experiment is a fail. And, in pushing the motor, he discovered one obvious weakness in a 3D printed plastic motor: heat. The plastic on his rotor melts.
But it’s a cool experiment and one that bears repeating and refining. He points us to another video where the maker, Christoph Laimer, had much better success at printing a Halbach motor.