These bits work good with a nail drill machine, I don't know if these should be fine with dremel too.
Model was designed for the polishing models from the bronze and copper filament. (You can see samples on the pictures above).
For the work you need 1 internal part and many externals.
Internal hole part have to be fixed after printing.
External part have 2 versions with 200u hole and 300u hole for the thick sandpapers.
For the beginners in the polishing: to get good results you need a lot of patience and time.
To get the best results with metal imitation filaments start with common sandpapers:
60 ->120->400->800 (When bits used I started from 120)
After this I used primitive nails polishing stuff that can be stolen from the wife or bought in all woman's shops. Cut it and set in bits.
Used steps 3,4 (sometimes 2) see in pictures below:
Finishing you can do with polishing soap or paste. (On the main pictures with samples I didn't use it but you can try to use and amaze me with better results =))