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Unread 13-03-2007, 13:32
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ZZII 527 ZZII 527 is offline
"Scale Electric Vehicle"
AKA: Shane Colton
FRC #0097
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Re: Banebots 42mm gearbox: Recommendations for use

I still think the higher gear ratios can be used, provided their function is speed reduction, not torque multiplication.

The torque that the final stage sees is entirely determined by the load. The FP motor can and will supply any amount of torque necessary to move your arm, whether it has to run near stall in a 64:1 gearbox or near full speed in a 256:1 gearbox. (Another way of saying this: If a 256:1 gearbox fails, switching it out to a 125:1 and/or changing to a weaker motor without changing anything else will not reduce the torque on the final stage and will probably fail even faster because of the additional speed of the arm.)

The teams for which the gearboxes have survived seem to be using them to drive light, well-counterweighted mechanisms through significant external reductions. Use your motors as speed sources and everything will be much happier.

I apologize if I am just restating the obvious.
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Last edited by ZZII 527 : 13-03-2007 at 13:50.