I have done quite a few videos related to using treadmill parts on shop tools to get variable speed. It is important to understand how your motor is rated so you will know if it will have enough torque for your project. Manufacturers don’t typically label their motors by torque they use horse power which is a sneaky way to make a less powerful motor with a higher RPM range look as good as a more powerful motor with a lower RPM range. This video shows you how to calculate torque and figure out if the motor you are wanting to use is up to the task.