gear box ratio?

We really need to know how to select the gear box ?, given other parameters: weight,motor size desired speed ?

randofo24 days ago

Typically gearboxes have a top speed, and force rating. Don't exceed those with your motor. :)

The easiest way is to get ones rated for higher than the output speed of your motor.

You also should keep in mind the size of the output shaft of the motor, and whether the gearbox has a keyed insert port, or its own output shaft.

If the gearbox has a keyed input port, does it match the motor's shaft?

If the gearbox has an output shaft, is it roughly the same diameter? If you get a motor with a really large diameter shaft and a gearbox with a really small one, you might have trouble finding pulleys (or whatever) with the correct diameter bore to accommodate both.

Determining gearbox ratio comes down to a matter of figuring out what your top motor speed currently is compared to how fast you want the motor to go once the speed is reduced. For instance, a motor with 2,000 RPM reduced through a 10:1 gearbox will have a speed at the other end of 200 RPM. The higher the number on the left, the slower the output.

Not sure what else you might be trying to understand.