First, you will need to know the pitch of the roller chain, or timing belt. For example, #25 roller chain is .25" (1/4") pitch and #40 roller chain is .5" (1/2") pitch. Timing belts are similar and you will need to search the specifications of your particular drive pulley pitch. Take this pitch and multiply this with the number of teeth on the drive pulley/sprocket. This will give you the number of inches around the pulley/sprocket. Now, take the number of steps per revolution that the motor will output. This will be the number of full steps that you motor produces (typically 200, or 1.8 degrees per step) multiplied by the microstepping per step to which the driver is configured. Divide this number by the inches that was calculated from the drive pulley/sprocket. Here is an example: If the motor produces 200 steps per revolution and I am driving it at 1/16 microstepping and my sprocket pitch is .25" with 9 teeth, my formula would be:
(200 steps * 16 microsteps) / (.25 inches * 9 teeth) = 3200
steps per revolution / 2.25 inches = 1422.222 steps per inch
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How do I configure my control program (i.e. Mach3, EMC2, etc.) for roller chain or timing belt steps per inch?