Thread: Gearing down?
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Unread 10-01-2002, 21:08
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What are you trying to do?

At what LOAD and at what VOLTAGE do you want the Chiaphua motors to run at 100 RPM's?

If you want them to run at 100 RPM you could certainly put enough friction on the shaft at a low enough PWM value to have them run at 100RPM.

If you want there Free speed to be 100 RPM you need essentially a 55:1 gear ratio. This is not terrible hard to get, though EXACTLY that is a bit tricky but doable.

In the kit you already have a 44:9 ratio.

Try this:
(44/9)*(72/16)*(60/24)=55/1
Viola!

First stage:
44:9 36 DP from the motor and the gear cluster from Atwood

Second stage:
72:16 -- use a 72T 32DP gear from McMaster and the 16 tooth gear connected to the 44T from the kit.

Third stage:
60:25 -- use a 60T and a 25T 24 DP gears from McMaster.

I don't know if you actually need the ratio you wanted but there you go.

Joe J.

P.S. The gears are sized about right to give you a nice long gear life -- you may check the last stage, the stess on that one MAY be a bit higher than you would like.