Electric motors for lift

Discussion in 'General Electronics Chat' started by Robin Mitchell, Dec 16, 2010.

  1. Robin Mitchell

    Thread Starter Well-Known Member

    Oct 25, 2009
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  2. Kermit2

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    The motor you selected is 46 grams. the propeller is just over 3.5 inches across.

    If you are very lucky that will lift itself of the ground, but won't have much left for any other lifting. The motor looks like it could handle another inch or two of propeller length.

    and going over the highest spec'd voltage (6V) would not be something you want to do.
     
  3. Bernard

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    Aug 7, 2008
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    Un loaded, the motor would probably self distruct from high RPM with drastic voltage increase before max current is reached; something like running an efficient series motor with no load. Looks like a low pitch prop, so may need more RPM, I'd increase V untill max current is reached.
     
    Last edited: Dec 16, 2010
  4. Robin Mitchell

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  5. Kermit2

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    That cuts your weight by 60% and only shaves 20% off the torque.

    If you have the choice, try both sizes of propellers, the larger one might be to much for the smaller motor.

    Have you considered the RPM vs the structural integrity of the plastic blades? 13,000 RPM is MUCHO centrifugal force on the tips

    1mm and smaller drill bits spin that fast or faster, but propellers? I haven't looked it up yet, but I'm guessing that is too much RPM for those blades. If one blade broke free it could hurt someone severely

    something lower than 6 or 7000 RPM would be better; and the bigger blade might need more torque than the small motor makes, but current measurements would be required to know for sure.
     
  6. Robin Mitchell

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    Then it hurts someone, theres no going foward if we dont take risks!
    Thanks for the info so far :)
     
  7. PackratKing

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    Jul 13, 2008
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    right idea, wrong rotation. >>> Air Digs -- Water Slaps.

    Your motor specifies clock rot. looking at shaft.

    Propeller shown is for counter-clock rot .


    the pitch of the blades on a prop. is designed to pull the craft thru the air
     
  8. Robin Mitchell

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  9. Kermit2

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    I think you answered your own question. So do it already and tell us how it works :)
     
  10. marshallf3

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    Jul 26, 2010
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    Props for RC planes are made to take extremely high rpms but remember that all propellers are designed for different purposes. Those for planes were designed to pull the plane through the air, they don't work by creating rearwards thrust. Helicopter blades work more as a revolving wing in that they provide lift due to the faster air speed over the top of the blade as opposed to the bottom. It's all a matter of experimentation to see what works best.

    If you want to see props take a look at http://www.towerhobbies.com
     
    Last edited: Dec 17, 2010
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