Hand Crank how to?

by jhendren
Tags: crank, hand
jhendren is offline
Nov28-11, 09:09 PM
P: 34
I want to create a handcrank to spin a DC motor at 24000 rpm. The DC motor is an 18V hobby motor from radioshack. Is this possible?
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xxChrisxx is offline
Nov29-11, 06:17 AM
P: 2,032
Possible yes, practical no.

You'll never be able to crank it fast enough with practically sized gearing.
Mech_Engineer is offline
Dec1-11, 01:51 PM
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P: 2,234
If you figured you would be able to spin a hand crank at about 60rpm (1 rev/sec), that means you'll need a 1:400 gearbox to step up the speed (and it will reduce your output torque by a factor of 400 as well). My guess is most hand-crank generators utilize a motor which spins at a couple of thousand rpm at most, meaning the gearbox is on the order of 1:20 or so.

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