Do you guys think this is a good motor to turn the gears? I also want to be able to change the speed so I guess I’ll need a rheostat or potentiometer. Which is better and what specs do I need? Will I need to match the voltage of my motor?
What batteries are good for this? I would like to save space so if I get two 9 volts = 18V will this be too much for my little 12V motor?
Is there a good package kit that has a motor and speed control together?
Can you take measurements as to what torque is required to rotate the crankshaft? This will help you get a better idea of the torque the motor needs to provide. Also, what is the speed at which you want the shaft to turn? It does not look like there is a lot of resistance. When you find these two values you can find a motor. Based on the nominal voltage, you can either choose a wall adapter or a battery pack. If you want to change the speed, we would suggest an analog motor controller with a potentiometer. 18V might be too much for your little motor. There are not many kits which include everything because the specs would be too specific for most people’s needs.
Take a look at the Tamiya planetary gear motor - you can adjust the gear ratios and unless the torque is quite high, at least one of them should work well.
