Sandpaper

After re-arranging the disks, the next step is to cut the sand paper. You can use ready ones if they happen to come in right sizes but I decided to cut one of my own. Just a piece of P100 grit paper, a sharp blade and a disk to be used as a template.

A bit smoother paper (P600 and up) could possibly eliminate the torgue-problems the tiny motor sometimes has.

Let's see if someone goes even further and seals the whole thing and makes a HDD-wet-sander.

Few words for the safety. Spinning things are often more or less dangerous and so is the case with this thing. I suggest you to use gloves, safety glasses and a bit of common sense when using this apparatus. HDDs have only tiny stepper motors, so this thing doesn't have much torgue. Nevertheless it runs fast enought to slit fingertips open and cause nasty cuts. Be careful!