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Rotate a Shaft - 60-120 Seconds Per Revolution - Bidirectional

I need to rotate a shaft very slowly.  Somewhere between 1 and 0.5 RPM.  I need forward and reverse.  I don't need position sensing.  External control will be two buttons -- forward and reverse.

I'm aware I could use a stepper motor and a controller, but that seems overly complex for my application.  I need close to 360 degrees of rotation and I'd *prefer* that it rotate in either direction as long as power is supplied, so a servo motor seems like a poor match.

There is a high probability it will get totally destroyed in the first few iterations of development, so something that's in the range of $10 is better than $100.  (It is at risk of getting fried by nearby high-voltage RF, if I mess up construction.)

What would be an appropriate motor/gear/whatever?


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But the cheapest option I can suggest is a 9gm Micro Servo modified for continuous rotation with encoders on it (to detect how much it has rotated). Even easier will be to just connect a servo to any micro controller you have (note, you'll need to modify the servo for continuos rotation as you also need it to run 360 degrees). However, I don't think I know about any option under $10 achieving 60 to 120 RPM

A stepper could be driven by a 293 or a 754410 with 2 wires from the microcontroller. And, you can get cheap steppers from printers that have been discarded. So, about the same price as a 9g servo.

Try the surplus motors from The Electronic Goldmine

I think maybe a timing belt might be a good approach, so long as I can find a non-conducting belt that is NOT metal reinforced.  It will provide the electrical isolation from the capacitor, and I can choose sprockets to turn the capacitor slow enough.

Is there a guide to timing belts and sprockets for newbies?