Q: I recently bought a set of old oak dining room chairs at a flea market. They’re well-constructed and sturdy but kind of dingy. What’s the best way to clean them up? - Janet Anderson, Portland, OR
A: I grew up watching my mom refinish antiques, and for several years during and after college I bought and sold antiques, so I’ve cleaned a lot of old wood finishes. Whether you’re working on chairs, a table, kitchen cabinets or wood moldings, it’s always best to start cleaning any unpainted wood surface with the least aggressive method and work your way up to more aggressive methods as necessary.
Dish soap, TSP and mineral spirits are the only products you need to clean most wood surfaces.
Start with a few drops of dish soap in a bucket of warm water. Dip a rag in the soapy water, wring it out and start scrubbing. Work in small areas, don’t soak the wood, and wipe each area dry after it is clean.
If soap isn’t effective, try using a liquid (phosphate-free) TSP cleaner. Follow the manufacturer’s instructions for mixing and application.
If you’re dealing with a heavy buildup of grime, dampen a rag with mineral spirits and scrub the surface. This will remove the grime from most finishes without removing any of the finish.
I’ve also had success with a homemade furniture-cleaner recipe that we used on many of the pieces we bought. It’s a three-part equal mix of turpentine, linseed oil and white vinegar. Scrub the piece with the mixture and wipe it clean with a soft cloth.
No matter which cleaner you use, always start by scrubbing with a soft cloth (pieces of old T-shirts work well). Be careful not to scrub so aggressively that you begin to remove the finish. If the cloth isn’t effective, try using a fine synthetic scrub pad (typically a white scouring pad). Be careful not to scrub so hard that you remove the finish down to the bare wood. You can also substitute 0000 steel wool if you can’t find a white scrub pad, but I prefer the synthetic pad because is doesn’t shed. Another tool that is helpful for getting into corners without damaging the piece is a 1/4-in.-dia. wood dowel with a point on one end. (Use a pencil sharpener to make the point.)
I don’t recommend using oil soaps unless you are sure you won’t be refinishing the piece in the future. These soaps leave an oily residue on the surface that prevents many topcoat finishes from adhering.
Also, don’t use any solvent that will soften or remove the finish, such as denatured alcohol, lacquer thinner, liquid paint/varnish strippers or products called refinishers for general cleaning or spot removing. These products remove layers of finish - potentially down to the bare wood. Save these products for when you want to strip and refinish a piece of furniture.
After the wood is clean, apply a coat or two of paste wax to add some shine and depth to the finish and to provide protection for the future. Congratulations on your find. Enjoy your new (old) chairs!