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Low RPM, High Torque on dry cell batteries

  1. Jun 8, 2015 #1
    Hello, Apologies I am not an engineer. I am hoping to find the approximate size of a system that rotates at a torque of 0.6nm but a rotation per minute of 1rpm. Ideally this would run off of dry cell batteries (e.g. 6xAA). Roughly how big would the gear system be to drop the RPM for this? How big would the motor be? Can you recommend any particular motor/gear system that would get the job done? Will dry cell batteries be sufficient? Any help at all in any of these questions would be greatly appreciated.
  2. jcsd
  3. Jun 9, 2015 #2


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    You can calculate the power required from the motor via:

    P = TĪ‰
    Power (Watts) = Torque (Nm) * angular velocity (radians/s)

    (Google how to convert rpm to rad/s)

    If this is a one off project one of, or a combination of a couple of these may work:

    Or you may need a rotary encoder.

    Or a stepper motor (and maybe a small, single stage gear box) may be better.

    It all depends on what your design needs to do.
  4. Jun 9, 2015 #3
    That's brilliant Billy_joule, thank you so much for your prompt and helpful reply! The links are really useful and will definitely get me started. Thanks so much for your help!
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