Finishing Wood Furniture

Whether you succumb regularly to the charms of thrift shop and garage sale treasures, or just acquired a piece of unpainted furniture to complete a room, you'll want to explore the fine art of furniture finishing. Even the most derelict cast-off or blah piece of unpainted furniture can be transformed into a cherished family heirloom with a little patience, elbow-grease, a few simple tools and the appropriate materials. Here's how:

Before You Start

* Assemble all the necessary tools and materials. (Don't forget brush cleaning solvents!) Be sure to have plenty of newspapers and clean rags on hand.
* Remove all hardware or non-fixed ornamentation.
* Read all finishing products' labels thoroughly.
* Be good to yourself - work safely! Protect hands with rubber gloves and wear safety goggles when working with products such as paint removers and bleaches, or when sanding. Always work outside if possible or in a well-ventilated room with all doors and windows open, away from sparks and open flames. Clean up promptly and dispose of soiled rags and newspapers in covered metal containers kept outside the house.

 

Stripping Finished Furniture
It is often necessary to remove all of the old finish from a piece of furniture before successful refinishing can be carried out. You can either strip it yourself, or take the furniture to a commercial establishment to do it for you, usually at a fairly reasonable price. These companies simply soak the piece in a vat of remover until the finish is softened and then they clean it. Here's how you do it yourself:

1. Buy a good quality grade of commercial paint and varnish remover. Although there are many types, in liquid or paste form, you may prefer to use one of the non-flammable, wax-free varieties, as they require no after-rinse or neutralizing when the job is done.
2. If you are using a liquid remover, pour some of it into a clean can.
3. With an old paint brush, spread the remover liberally on one small section of furniture at a time. Stroke in one direction only.
4. Allow the remover to soak into the surface until the finish has been softened all the way down to the wood - usually 5 to 15 minutes.
5. Scrape off the softened finish with a dull putty knife. On carved or grooved surfaces, pointed sticks, coarse twine or an old toothbrush can greatly aid the removal process. Wipe off your tools frequently on newspapers. On very old furniture with many coats of paint, several soak and scrape operations may be required.
6. When stripping an open-grained wood such as walnut, oak or mahogany, you must also remove the old finish from the pores. Saturate a pad of medium gauge steel wool with remover and rub the wood with considerable pressure, working with the grain. A stiff bristle brush is also helpful.
7. After the finish has been removed, wipe the wood dry with clean cloths. Follow directions on the remover label. A final wipe with mineral spirits or turpentine is recommended since some removers contain wax and this must be removed from the wood surface.

Sanding
All stripped or unfinished furniture must be sanded as smooth as possible before any finish is applied. This all-important step will, to a great degree, determine just how professional-looking your finished project will be.

1. Sand with progressively finer grits of sandpaper, starting with medium or fine grades, and finishing with very fine. Always rub with the grain to avoid scratches that may show through the finish .

There are many different types of sandpaper available, but generally, open coat aluminum oxide paper is preferred for furniture, since it cuts faster and lasts longer.
2. Use a sanding block on flat surfaces to prevent unevenness and rounded edges. You can buy one or make one from a block of wood with a cloth or felt pad attached to the bottom under the sandpaper.
3. For curved or irregular surfaces, cut sandpaper or emery paper into strips and use it without a block. Pads of medium to fine steel wool work well on difficult areas, too.
4. If you use an electric sander, it should be a belt or reciprocal type, as circular sanders do not sand in a straight line. They are likely to leave marks on the wood surface which show through the finish.
5. After sanding is completed, thoroughly remove all dust. The best way to do this is with a tack rag. You can buy one at your paint dealer or make one from a piece of lint-free cotton cloth. Just dip the cloth into varnish that has been diluted with an equal amount of turpentine or mineral spirits. Wring the cloth until almost dry.

Bleaching
This procedure is necessary only when you wish to lighten the wood's natural color, or to remove undesirable stains. For best results, use a commercial wood bleach. Most are two-part solutions which are either intermixed or applied in successive steps (read the label). Use rubber gloves and keep bleach out of the eyes.

1. Apply the bleach with a brush or sponge. The label instructions will tell you whether the two solutions should be applied separately or mixed before applying.
2. Rinse or neutralize, if necessary (see label).
3. Allow the piece to dry overnight - at least 12 hours.
4. Sand lightly with very fine sandpaper to remove raised grain. Wipe all dust from the wood.

Staining
Stains are used to color the wood to emphasize its grain, to make one type of wood look like another, to create uniform color in a piece which is made up of more than one kind of wood, or to tint patched areas to match the rest of the piece. Most stains should be used only over bare, smoothly sanded, clean, dry wood.

Of the many types of stain available, two seem to be most popular with do-it-yourselfers:

Penetrating resin stain is actually a finish system. It is a clear resinous coating that sinks deep into the wood pores imparting a somewhat darker appearance to the natural wood. Simply apply it generously to the surface with a rag or brush, let it soak in for 30 to 60 minutes, depending on the darkening effect desired, and wipe off the excess with clean rags. Since penetrating resin stain is also a finish, a coat of wax is all that's necessary once it dries.

Pigmented oil or wiping stains are the most easily controlled. Even if a piece or section gets too dark, it can be lightened with minimum effort by rubbing with turpentine while still wet, or by sanding when dry. Before using a oil stain, wipe off the smoothed surface with a clean cloth dampened with turpentine or mineral spirits. Then wipe the entire surface with a tack rag. Then just apply the stain with a brush, wait 5 or 10 minutes, and wipe off excess with clean rags. Let it dry for 24 hours before finishing.

Both of these types of stains are available in a wide range of colors. Shades of the same type can be mixed to produce even more color variation. Be sure to test colors on similar scrap wood first. To get an idea of what the finished piece will look like, coat the test scrap with the clear coating you plan to use, too. Here are some additional staining tips:

1. For best results when using an oil stain, apply a thin sealer coat to the bare wood first. This gives a more uniform color effect. Your paint dealer can recommend one that is suitable.
2. Stain and wipe one full section or panel at a time.
3. Do less conspicuous areas first, saving the front faces and tops for last.
4. In the final clean-up operation, wipe in the direction of the grain.
5. Since end grain wood will absorb a far greater amount of stain than other surfaces, wipe it with linseed oil or a clear coating first to slow down absorption.

Paste Wood Fillers
Open-pore woods, such as walnut, oak and mahogany, require the use of a paste filler if a super-smooth finish is desired. These fillers are available in colors. You can also buy a natural or neutral filler and tint it with the stain you've used on the piece or with pigment from tubes. Here's how to use it:

1. Put some of the paste filler into a clean can and thin it by adding turpentine or mineral spirits, stirring until the mixture is the consistency of heavy cream. Be sure the wood is clean and that all dust is out of the wood pores.
2. Brush the filler onto the workpiece with a short, stiff-bristled brush. To assure that all open pores are filled, stroke on the liquid first with the grain, then across the grain.
3. Allow the filler to set until it loses its shine - about 20 to 30 minutes.
4. Remove the excess filler with a rough-textured cloth, such as burlap. Wipe first across the grain to force the filler into the pores. Then, do all final wipes gently with the grain.
5. Finish by wiping down the entire surface, with the grain, using a clean, lint-free cloth.
6. Let the piece dry or at least 24 hours before proceeding further.

Finishing
Though there are many finishes you can use, two types are perennial favorites with do-it-yourselfers because of their reliably satisfactory results:

Linseed oil finish is time-consuming to apply, but gives the wood a beautiful, mellow lustre. Although it is not highly water-resistant, this finish will withstand hot dishes. Also, it is less likely to show scratches than would a varnish finish.

Often, this finish is applied directly to raw wood, but keep in mind that it will tend to darken the wood in most cases. If you decide to stain first, a water stain is preferable as it will leave the wood more porous than oil types, which tend to fill the pores. Follow these steps for best results:

1. Purchase boiled linseed oil from your paint dealer.
2. In a clean can, make a mixture of two parts of the oil to one part turpentine or mineral spirits.
3. Warm the mixture by standing the can in a larger container which can be kept filled with hot water.
4. Spread the oil mixture liberally over the surface with a thick pad of clean, lint-free cloth. Continue applying and rubbing it until the surface no longer absorbs oil. Discard rags as they become oversaturated. To avoid spontaneous combustion spread the rags out or immerse them in a pail of water.
5. Using a piece of tightly woven cloth, buff the surface continually until a finger touched to the surface does not pick up any oil.
6. Let the piece dry overnight and repeat the entire process again. Opinions differ on how many coats to apply, but generally, a minimum of three applications is necessary. The more you apply, however, the more attractive and durable the finish will be.

There are many new, improved varnishes or clear coatings available for furniture finishing. Some are very pale for use on light colored furniture. Others offer resistance to foods and alcohol. Ask your paint dealer for recommendations.

To apply varnish:

1. Work in as dust-free an environment as possible. Although there are a number of varnishes that set dust-free in one-half hour or less, some take much longer to dry. Naturally, the more dust that settles on the surface, the more time will have to be spent smoothing the piece later.
2. Use a tack rag to remove every possible trace of dust before applying the first coat.
3. Thin the first coat of varnish with turpentine, mixing gently with a clean stick. (Successive coats are then applied as the varnish comes from the can. Do not stir varnish, as this causes air bubbles.)
4. Apply varnish with a good quality natural-bristle brush. Dip the brush into the varnish only one-third the length of the bristles. To remove excess varnish from the brush, tap the bristle tips lightly against the inside of the container. Do not drag the bristles across the rim of the can, as this causes tiny bubbles to form, making it extremely difficult to create a smooth finish.
5. Brush the varnish on the surface, then work the brush at right angles to the original direction of application.
6. Finally, tip off with an almost-dry brush held at a 30 degree angle to the surface.

7. Allow the varnish to dry completely - 48 hours is best. Then, sand lightly with the finest grade of sandpaper or steel wool available. Dust well and wipe with a tack rag. Repeat this step between each coat. (Normally, one thin coat and two from the can will suffice.)
8. Let the final coat cure for at least one week before applying paste wax.

Enameling
Many a white elephant has been transformed into a decorator's dream with a coat or two of shiny or matte enamel in some marvelously off-beat color. Enamel is also a good finish choice for inexpensive unpainted furniture when paint quality wood has been used, or for furniture to be used in children's rooms or other areas where frequent damp wipings will be necessary. But, in today's sleek, contemporary interiors, painted furniture is right at home in any room. And, because enamels are available in a wide range of glosses - from elegant eggshell to the dramatic wet look - and in a rainbow of colors, almost any effect you want is possible.

There are two types of enamel -- oil-based and latex (water-thinned). Usually, the oil-based type produces the best results on furniture. This type is available in both regular brush-on and spray formulas. Spray enamel is especially good for small projects and intricately patterned surfaces.

Follow these steps for a beautiful enamel finish:

1. If painting over a previously finished surface, sand lightly with fine sandpaper; then, thoroughly clean off old wax, grease or dirt with detergent or solvent. Rinse, and wipe dry.
2. If applying enamel over an unfinished piece, the surface should be sanded as smooth as possible. If the piece is a hardwood species with open pores, use a natural paste filler before proceeding (see Paste Wood Filler section). If you're painting a softwood, it is best to apply a sealer first. Ask your paint dealer to recommend the best products for your particular project. Following sealing, rub lightly with fine gauge steel wool. Dust the piece carefully and wipe with a tack rag before going on to the next step.
3. Apply a coat of enamel undercoat. After it dries, rub lightly with fine gauge steel wool and dust thoroughly.
4. Brush on one or two coats of enamel, using a good quality enamel brush in the widest possible width appropriate to the surface. Whenever possible, work with the surface in a horizontal position to prevent runs or sags in the enamel. If two coats are used, it is advisable to sand lightly and wipe between coats.

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