Grommet Drive
Grommet Drive for a CD-ROM Tuning Dial
You can make a fairly good reduction drive from an old CD-ROM disk and a rubber grommet. You can make it even better by adding some compression to the grommet so it grips the CD-ROM edge more reliably.
This is a simple grommet drive on the edge of a CD-ROM tuning dial. It works but tension has to be kept against the disk to keep it from slipping.
This is the grommet drive with compression added so the sides of the grommet grip the CD-ROM disk. This one doesn't have the tendency to slip.