ChainringGen is an OpenSCAD script to generate chainrings of different sizes and bolt standards. However, it only worked for evenly spaced bolts. I added support for asymmetric bolt patterns. Users can check Sheldon Brown for degree measurements of commonly available bolt patterns—i.e. Shimano 110 BCD bolts are 70/110° apart—or make their own.

Future iterations might allow users to configure cutouts or select different tooth profiles, updating ChainringGen for the thin chains that come with 12-speed+ drivetrains.