This project ist based on Dark Sky Geek's excellent ASCOM OAG design (https://github.com/jlecomte/ascom-oag-focuser). I redesigned the mechanical parts to better fit my astophotography setup and to make the build easier. To print the gears use hole compensation to get a tight fit with the stepper motor and the helical focuser. Print the gears with 0.1mm layer height. All brass inserts are M3.