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Is it okay to increase DC motor RPM by using higher voltage

  1. Aug 22, 2013 #1
    Hello guys
    I'm looking for a motor for my arrow saw project. I would like to use it to cut carbon arrows. Found one motor in the shop that is pretty small and will work perfectly with my jig. But it's rpm's are only 1650 and I need at least 8000 RPM. Is it possible to increase the motor RPM's by increasing voltage? Motor specs:
    Voltage - 74 DC
    RPM - 1650
    Amps - .4
    Hp - 1/75
  2. jcsd
  3. Aug 22, 2013 #2


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    I would expect that you can exceed the specs a bit (like 2000 instead of 1650), but I really doubt that you can get 8000 RPM directly from the motor - I will probably ruin the motor, and it can be dangerous for you as well. There is a good reason why the specifications do not quote a larger value.
    Gears might work.
  4. Aug 22, 2013 #3
    That's what I thought. Looks like I need to go out shopping :-)
  5. Aug 22, 2013 #4

    jim hardy

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    Look for junked treadmills. I gave got several 6,000 RPM 90 volt DC motors out of them. They ran okay on full wave rectified housepower with no filter capacitor, which would be ~120 VDC unfiltered so probably puts the motor in your speed range . An ordinary lamp dimmer gave me speed control.

    Another thought - Vacuum cleaner motors run in the 10,000 rpm range but are noisy. You'd have to put an enclosure around it.
  6. Aug 22, 2013 #5
    Another possibility is a blender ( I broke my 1000W Ninja blender under warranty and got the motor out of it...) or look for a damaged drill or dremmel type tool.
  7. Aug 22, 2013 #6
    Blender sounds good. I might even have one :-)
  8. Aug 23, 2013 #7


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    It is best to avoid gears at those speeds and use direct drive, or an air motor.
    High RPM motors are long and thin. Slow speed motors are short and fat.
    A die grinder might be a good solution. Also a small router.
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