Dulling semi-gloss paint increases the surface area of the paint for repainting. A fine sandpaper dulls the shine as it makes tiny scratches in the paint. These scratches are hard to see, but the loss of the shine is noticeable and new paint will have more surface area to bond with. Oil-based semi-gloss creates a little bit of dust when sanded, and latex semi-gloss doesn't. Latex has a tendency to gum up when sanded, because the friction causes heat. Sanding lightly and slowly is the best technique for dulling semi-gloss paint.
Things You'll Need
- 220-grit sandpaper
- Tack cloth
Fold a piece of 220-grit sandpaper into a square and grip it in your hand.
Sand the shiny, semi-gloss surface up and down and from side to side until the shine is gone and a dull luster is revealed. Sand any grooves by folding the sandpaper into smaller squares and angling the paper down toward the ground. Pinch the ends of the paper in your fingers and slide the sanding corner of the paper up and down or side to side in the groove.
Go over the dulled surface with a tack cloth to remove all dust film. The semi-gloss can now be primed and painted.