Big and small gear refers to Gregs/Wade extruders. Set both numbers as 1, if you don't use a geared extruder.
If you have a gear on the stepper shaft which is flat then use it's outer diameter. When the gear is hobbed, measure the diameter of the hobbed part.
-Olaf
If you have a gear on the stepper shaft which is flat then use it's outer diameter. When the gear is hobbed, measure the diameter of the hobbed part.
-Olaf