Wash and sand old, painted woodwork before repainting. If the paint is in a bad condition, it is best to strip it off before repainting.
1. Wash with TSP: If rough, and using medium sandpaper. Wipe with lint-free cloth dampened in turpentine.
2. Paint the topcoat onto the clean surface. For a different color, apply an undercoat, let it dry, and repaint.
SMOOTHING BETWEEN COATS
As you paint, small bristles, dust particles, and other debris will inevitably become caught in the wet, painted surface. Check the surface after each coat. If you spot blemishes, sand the surface between coats.
1. When dry, inspect the area for blemishes. Smooth the area, using fine sandpaper wrapped around a cork block.
2. To check that all the bumps have been removed, rub the palm of your hand over the surface. Brush away any dust.
3. To remove any last traces of dust, rub the area with a piece of damp, lint-free cloth. When the surface is dry, repaint.