Designed work with a 25mm dc motor like this one:
https://www.makerstore.com.au/product/mb-elc-sgm-25d/

I also used a 695zz bearing on the non motor end.

All the parts have heat set inserts, and are held together using M3x8 SHCS.

I used very fine fishing line for the cable. There is a hole through the end of the spool with a pair of holes in the flange for retaining the line.