The concept worked really well, it was the mounting of the motor to the heater that was tough. The magnets held the NEMA to the baseboard, but transferred way too much noise. Now that I have a 3D printer, I would just print a bracket to hold it and everything would have been perfect. I’ve since moved though. You could go with 3DHubs and have them print a bracket for your setup. Worth it.

Also, I would 3D print a pulley that fits directly onto the shaft, instead of boring out an existing pulley. And making the belt by hand (staple and pray) was a weak link. So, going back, printing a bracket would reduce the noise and I could choose a premade belt and make the bracket height accommodate that distance.

I looked at the relay option, and since it was a dual leg 120v circuit, that meant two 20A SSD relays — expensive and still scary.

Curious to hear what you end up doing, keep me posted!