- 1). Use your hammer and nail set to sink any nail heads that are sticking up on the floor, so they don't rip your sanding screens. Thoroughly clean the floor of any dirt or dust.
- 2). Set up your floor polisher with its 60-grit sanding screen. (Systems vary, but generally the polisher will just sit on top of the screen, over a pad that comes with the screen.) Starting at the far corner of the room, move the machine slowly but steadily forward and back along the floorboards, going in the same direction as the boards. Do the whole room. Vacuum up the dust.
- 3). Switch to your 80-grit sanding screen. Repeat the process. Vacuum up the dust. Then screen the floor a third time, with your 120-grit screen. Vacuum the dust. The floor's surface should now be free of any gloss shine, but the stain of the floor should be unaffected.
- 4). Load your palm sander with 60-grit sandpaper. Use it to sand in the corners of the room, where the polisher couldn't reach. Re-sand the corners with 80-grit and then 120-grit sandpaper. Make sure not to sand into the wood itself, but just the surface polyurethane.
- 5). Vacuum up all the dust. Go over the floor with tack cloths (slightly sticky rags) to take up any remaining dust and debris. The floor is now ready to be re-glossed.
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