those heavy duty motors are the stepper type. They can adjust different speeds. You will see a bunch of wires going to them. I sell these motors on ebay for robots, cnc, hobbies. Get a box of them and ship in flat rate box. The large motor I tear down and remove the copper. It is very easy. Yes I save all my screws and little metal pieces. I will love to see the scrap yard faces and when bring a truck load of screws.
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