You have 4 points of gearing:
Just forget the complexity of this because what matters is the steps per rotation and that roller the object is resting on. Steps per rotation and the roller diameter are the two adjustable values to play with to dial in this type of rotary. Independently, neither one of them have to be technically correct. The two values just need to work together to calibrate the movement.
Plug in an accurate diameter for your test object, then go to work with the steps per rotation and roller diameter. (Also make sure you have enabled the rotary in Lightburn AND enabled the rotary on your machine usually by way of a switch that transfers the driver to a panel mounted plug).
