How to Restore Glazed Porcelain Tiles
- 1). Run your vibrating hand sander and aluminum oxide sandpaper over the surface of the porcelain tiles. Move the sander slowly and press firmly to dull what's left of the old glaze as much as possible. Don't sand the grout lines.
- 2). Wipe off the surface of all dust, using a dry rag.
- 3). Brush polyurethane over each tile, using a finishing brush. Brush it on in thin, even strokes, all going in the same direction. Take care to keep bubbles from forming. Don't gloss over the grout lines, just the tile surface. Let the polyurethane dry for 24 hours.
- 4). Buff the surface by hand with fine sandpaper, getting the shine dull so the next coat will adhere. Brush off the dust.
- 5). Apply a second layer of polyurethane in the same was as you did the first. Let it dry, sand it by hand and wipe off the dust.
- 6). Apply a third and final layer of polyurethane. Let it dry.
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