Caring for Wood Furniture by Its Finish

Most advice about caring for wood furniture is really advice about caring for its finish. The wood itself is sealed under a coat of lacquer, varnish, polyurethane, shellac, oil or wax, and that coat is what you clean, protect and occasionally repair. Different finishes need different care, and a product that is fine on one can damage another, so the first job is working out what you have.

Identifying the finish

Try these on a hidden spot, such as the back of a leg or the underside of a drawer.

The water test. Put a drop of water on the surface. If it beads up and sits there, the piece has a hard surface finish such as polyurethane, lacquer or varnish. If it slowly soaks in and darkens the wood, the finish is oil or wax, or it has worn through.

The solvent test. Dab a cotton swab with denatured alcohol. If the finish turns soft and sticky within a minute, it is shellac, common on antiques. If nothing happens, try acetone. Lacquer softens with acetone, while polyurethane and most modern varnishes resist both.

Many factory-made pieces from recent decades have a lacquer or polyurethane finish. Older antiques are more likely to be shellac. Furniture that looks matte and feels close to raw wood is often oiled.

Polyurethane, lacquer and varnish

These are the toughest finishes. Dust with a soft, dry microfiber cloth, which picks up dust instead of pushing it around. For grime, wipe with a cloth barely dampened with water and a drop of mild dish soap, then dry immediately. Silicone-based spray polishes add shine at first but build up a film over time and can make future refinishing difficult, so most restorers advise avoiding them. A paste wax applied once or twice a year adds a protective layer if you want extra sheen.

Shellac

Shellac is beautiful but sensitive. Alcohol dissolves it, so a spilled drink or perfume can leave a dull spot, and water and heat can leave white marks. Dust gently, avoid water wherever possible, and use paste wax rather than liquid polish. Keep coasters and placemats in constant use.

Oil finishes

Oiled furniture, including much Scandinavian and mid-century pieces, is finished with oils such as tung or Danish oil that soak into the wood. It looks natural but offers less protection. Clean with a barely damp cloth, and every few months, or when the wood looks dry and pale, wipe on a thin coat of the same oil, let it soak in for the time on the label and wipe off every bit of excess. Rags soaked in these oils can heat up and catch fire as they dry, so lay them flat outdoors to dry or put them in a sealed metal container of water before throwing them away.

Waxed pieces

Waxed finishes are buffed rather than cleaned with liquids. When the shine fades, apply a thin coat of paste wax, let it haze, and buff with a soft cloth. Fingerprints and smudges usually buff out without adding more wax.

Fixing common problems

White rings come from moisture trapped in the finish, not in the wood. They often fade if you lay a cotton cloth over the mark and pass a warm, dry iron over it for a few seconds at a time, checking constantly. A hair dryer on a low setting works too.

Dark rings mean water has reached the wood itself, and usually need refinishing or professional help.

Heat marks from a hot dish are usually white or cloudy too and respond to the same gentle warmth. If they don't, very fine steel wool (grade 0000) rubbed lightly with a little paste wax, following the grain, can dull the mark on a hard finish. Test on a hidden spot first, since it can change the sheen.

Sticky residue from labels or tape usually lifts with a little mineral spirits on a cloth, or by rubbing gently with a dab of paste wax.

Light scratches can be disguised with a matching furniture touch-up marker or wax stick. Rubbing the meat of a walnut over a fine scratch in a medium-toned wood is an old trick that can darken it slightly.

Reviving a neglected piece

Secondhand and inherited furniture often arrives dull, sticky or grimy from years of polish and fingerprints. Before reaching for stripper, try cleaning. Mineral spirits on a soft cloth, tested first on a hidden spot, removes old wax and grime from most hard finishes without harming them, and the piece often looks far better once the buildup is gone. Work a small area at a time and wipe dry. Avoid this on shellac if the solvent test showed it softening, and never use it near an open flame.

If the finish is crazed, cracked or worn through in places, a product sometimes called a restorer, a tinted oil and solvent blend, can even out the color without full refinishing. Stripping and refinishing is the last resort, and on antiques it can significantly reduce value, so get advice first if the piece may be old or valuable.

Protecting it day to day

Sunlight fades and yellows wood over time, so keep valuable pieces out of direct sun or rotate items on top of them. Wood swells and shrinks with humidity, and very dry indoor air in winter can cause cracks and loose joints, so keeping humidity moderate helps. Place furniture away from radiators and heating vents, use felt pads under objects, and lift rather than drag pieces when moving them.