[asid61]

If you have a mill, and tell me your specs, and go with a CIM or Minicim I can whip up a quick gearbox CAD for you if you don't know how to design one or don't have time to learn.
I would just bag what you can and just buy a COTS product. Design everything you can and get some driver practice in.
If you can use 1 cim instead, it's easier than bags, as the bags are tricky to mount to traditional frc gears.