Did you know you could paint almost anything? Here's some tips for painting unusual surfaces.
Masonry, such as brick or stone:
Prep: scour unpainted surface with a sponge or nylon brush and warm, soapy water. Let dry overnight. On previously painted surfaces, use a wire brush to remove chips or flakes, then smooth uneven surfaces with 100-grit sandpaper. Clean as above.
Coat: seal pores with a water-based primer designed for masonry, and coat with latex paint. Use a thick-nap roller, and use a brush to cut in along the edges or to get paint into deep crevices.
MDF (medium-density fiberboard, used for built-in bookcases and cabinets, and interior trim)
Prep: Do not wash the surface because it can become "fuzzy". Sand unpainted material with 150-grit sandpaper to give it tooth. Factory primed material is ready for paint.
Coat: to keep material from swelling, use shellac or oil-based primer, covering the cut edges with two coats. Top off with latex paint, using a small brush to cut in and a short-nap roller (up to 1/2 inch ) for coverage on large areas.
Metal (such as radiators, heat registers and tin ceiling tiles)
Prep: Clean unfinished metal with soap and water and a sponge. Immediately blot dry if iron or steel. On already painted metal, use a wire brush to remove loose chips, then smooth uneven areas with 100-grit sandpaper before washing.
Coat: Use an oil-based primer on ferrous metals (those containing iron) to prevent rust, or a water-based metal primer on nonferrous surfaces.
Choose a latex spray paint, one formulated to handle heat, where needed. Avoid drips by applying several thin coats, letting each coat dry in between.
Plastic: any type, such as plastic furniture, switchplate covers, etc.)
Prep: Wipe surfaces with an ammonia-based cleaner, rinse with a damp cloth and let dry. Rough up glossy or previously painted plastic using 150-grit sandpaper, so it will accept new paint.
Coat: Apply a bonding primer designed for plastic, and coat with latex paint. A wider brush covers in a few passes, minimizing brush strokes. If you're not confident about your brush technique, try a 4-inch foam roller or a spry paint made for plastic.