Quote:
Originally Posted by BigElCat
Bah ! One has to take what I say with a 'grain of salt'.
When folks talk about money, 40M is $40,000, not 40 million. (and this supports my argument somehow)
Guess I was talkin' about metric RPM. It made a 'whirr' noise. (grin) Minimal down draft, lots of lift.
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Everywhere I looked, $40M is 40 Million dollars. If its $40,000 usually designated as $40K.
Also as to high rpm motors, we have a CNC that is capable of 40,000 rpm but we don't run it over 15K rpm because, at higher rpm's the torque (force required to shear metal) is greatly diminished. Also familiar with 80K rpm motors, but they are small and usually pneumatic because an air blanket is used as a bearing (no metal to metal contact and the air needs to be expunged anyway).
As to rotors capable of lift, making a bearing to handle the thrust and vibration will be a far bigger challenge.