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

  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. mfb

    Staff: Mentor

    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 There is a good reason why the specifications do not quote a larger value.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. That's what I thought. Looks like I need to go out shopping :-)
  5. jim hardy

    jim hardy 5,460
    Science Advisor
    Gold Member
    2014 Award

    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. 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. Blender sounds good. I might even have one :-)
  8. Baluncore

    Baluncore 3,305
    Science Advisor

    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.
Know someone interested in this topic? Share this thead via email, Google+, Twitter, or Facebook

Have something to add?

Draft saved Draft deleted