For finishing, I am in love with the 3M Bristle discs. They aren’t
my choice for removing heavy marks, but they are definitely my choice
for finishing pieces!
My general routine is to use sandpaper, 320, 400, 600, on the split
metal mandrels. You slip an edge of a strip of sandpaper in the slit
of the mandrel and wrap it around. Then the rotation of the flexshaft
keeps the sand paper rolled in place while working, and you tear off
any worn parts when needed. Extremely economical.
Next up is using the Radial Bristle Discs, and which ones depend on
how high I want to finish. Usually that’s enough for me, but I’m not
after a super high mirror shine all the time.
I’m not afflliated with Rio, nor am I saying they’re the best place
to get these - I just want to show you what they look like. There are
a number of retailers, hobby shops and hardware supply stores that
might carry these at greater or lesser cost.
3M Radial Bristle Discs:
Hope this helps some.
Cheers, and good luck!