Examine the dirt that covers that piece of old wood furniture to decide the best method to clean it. When cleaning with a water wash, avoid over-soaking the cloth, as too much water can weaken or soften old glue. For cleaning waxed finishes, you may need to abrade the surface to get rid of the old wax. After cleaning, you can over-coat old finishes with a new one if the furniture is in good shape and it simply needs an upgraded finish. But on collectible antiques, it's best just to dust.
Dirt and Oil Buildup
To effectively clean chairs, tables or old dressers with a water-wash method, the water must be hot enough that you have to wear rubber gloves. To 1 gallon of hot water, add 4 tablespoons of boiled linseed oil and 2 tablespoons of gum turpentine. Dip a soft cloth in the solution and wring it out so that it is damp, but not dripping. The turpentine and hot water gets rid of built-up waxes, polishes, oils and dirt. The linseed oil replaces worn spots in the finish, as many old pieces only had this type of finish. Wipe dry with an additional clean, soft cloth. Add lemon oil or other polish for the finish.
Grimy Finishes and Oily Fingerprints
For really old pieces or antiques on which you're worried about the old glue in joints, to a glass jar with a lid, add 3/4-cup boiled linseed oil and 1/4 cup of gum turpentine. Secure the lid tightly on the jar and shake it vigorously to mix the ingredients together. In a clean, small tuna can, add hot water. Pour some of the turpentine and linseed oil mixture onto the top of the hot water. Dip fine steel wool, number 0000, into the small tuna can. Rub the covered steel wool onto the surface of the wood, working in direction with the grain, but do not apply too much pressure. Wipe dry and polish with a clean cloth.
White Spot Cleaning
Toothpaste applied to number 0000 steel wool or a soft cloth and rubbed onto the surface of the wood can remove white spots on the surface of old furniture. Work the toothpaste across the surface of the wood in the direction of the grain, buffing carefully. Use a clean soft cloth to remove the toothpaste, and polish with your favorite paste wax or lemon oil. This method applies to small or simple white spots only.
Wood Floors and Countertops
To effectively clean wood floors or wooden countertops, mix a 1/2 cup of vinegar into a bucket filled with a gallon of warm water. Use a sponge mop and dip it into the mixture, but thoroughly squeeze it so it is almost dry. The point is to avoid over-wetting wood floors or countertops with water. Immediately wipe up any overly wet or streaked areas. Avoid oil soaps when cleaning wood, unless you test it in an inconspicuous area first, as these can blacken old woods.
When Not to Clean
If you have an antique and you damage its worn finish, it can decrease the value of the piece. Instead of applying oils to these surfaces, which can darken the wood or ruin the finish, lightly dust with a moistened cloth followed by a dry cloth. Collectors prefer the finish and the patina of the furniture as-is; cleaning can remove the finish or even gently abrade the surface, which can affect its value. When in doubt as to the value of an antique, Karen Keane, overseer of an upscale auction house and sometime appraiser for the "Antiques Roadshow," recommends that you leave the finish as it is.