Wood is a beautiful material, but not all wood is equally beautiful. The choice woods are prized chiefly for the beauty of their color and grain; the common furniture woods are less desirable not because they don't work as well but because they don't look as nice. Antiques, whether hardwood or softwood, are often beautiful simply because the wood has acquired a patina that new wood doesn't have. In furniture refinishing, one great equalizer is used to make the wood look better: stain.
Staining is done for a variety of reasons. Properly used, stain can emphasize the wood grain and give a light wood character. It can make a new wood look old or a common wood look like a rare one. It can pull together a two-wood piece, restore color to bleached areas and change or deepen the color of any wood. Staining is not always advisable, but it can solve a lot of problems.
Before you stain any piece of furniture, take a good look at it. If it's made of cherry, maple, mahogany, rosewood, aged pine, or any of the rare woods, the wood should probably not be stained; these woods look best in their natural color. If the wood is light, with a relatively undistinguished grain, it may benefit considerably from a stain. Beech, birch, poplar, ash, gum, and new pine are usually stained before finishing. Some woods, like oak, are attractive either stained or unstained. In general, it's better not to stain if you're not sure it would improve the wood.
The type of wood is not the only guideline for staining; your own preference should be the deciding factor. To get an idea how the piece of furniture would look unstained, test an inconspicuous spot -- on the bottom of a table, for example -- with whatever finish you plan to apply. The finish itself will darken the wood and bring out the grain. If you like the way it looks, there's no need to stain the wood. If you want a darker color or a more pronounced grain pattern, go ahead and stain it.
Once you know what type of wood you are working with, it will be easier to choose a stain that will enliven and restore the wood. There are many types to choose from.
Choosing a Stain
Several types of stains are available: wiping stains, water-base stains, varnish and sealer stains, NGR stains. Some stains are combined with a sealer, and these are usually labeled as stain/sealers. Not all are easy to use or guaranteed to give good results, so take a few minutes to plan and read the labels.
The first consideration is the finish you plan to use. Most finishes can be applied over most types of stain, but polyurethane varnish cannot be applied over some stains. If you want to use a polyurethane finish -- and this type of finish is both good-looking and very durable -- look for a stain that's compatible with polyurethane. If you can't find a compatible stain, you'll have to apply a clear penetrating resin sealer over a noncompatible stain. Varnish can be applied over this sealer if you want a shiny finish.
The second consideration in choosing a stain is the job you want it to do. The most commonly used furniture stains are based on pigments mixed in oil or turpentine, or on aniline dyes mixed in turpentine, water, alcohol, or a volatile spirit. Other types of stains include varnish stains, sealer stains, and organic stains.
Pigmented Oil Stains
The pigmented oil stains are nonpenetrating. They consist of pigments mixed in linseed oil, turpentine, mineral spirits, or a similar solvent. They are sometimes also available in gel form. They are inexpensive and easy to apply, but unless the grain of the wood is very open, they usually blur or mask the grain pattern.
These stains usually don't work well on hardwoods but can be used for slight darkening on close-grained hardwoods, such as maple. The lightening stains are pigmented oil stains. Pigmented oil stains are applied by wiping and are removed after the desired color is achieved. The intensity of the color is controlled by the length of time the stain is left on the wood. Drying time can be long, and the stain must be well sealed to prevent bleeding through the finish. The wood should also be sealed before application. The colors fade over time.
Penetrating Oil Stains
The penetrating oil stains are very popular; they consist of aniline dyes mixed with turpentine or a similar solvent. They are inexpensive and easy to apply, but they tend to penetrate unevenly. For this reason, they don't work well on hardwoods and are best used on pine and other softwoods. They can be used for slight darkening on close-grained hardwoods, such as maple.
Penetrating oil stains are applied by wiping and are removed after the desired color is achieved. The intensity of the color is controlled by the length of time the stain is left on the wood. Drying time is relatively long, and the stain must be well sealed to prevent bleeding through the finish. This stain is very hard to remove once it's dry. The colors are rich and clear, but they fade over time.
NGR (Non-Grain-Raising) Stains
The NGR stains consist of aniline dye mixed with denatured alcohol or a volatile spirit, such as methanol. They are expensive, and they can be difficult to use. Alcohol-base stains fade over time and must be sealed well to prevent bleeding; they cannot be used with shellac. Spirit-base NGR stains don't fade or bleed, and they produce a more uniform color.
Alcohol- and spirit-base NGR stains dry very quickly. Apply them with very quick, even brushing. Repeated thin applications are best to minimize overlaps. One color can be applied directly over another, but too dark a color must be bleached out. NGR stains are recommended for use on hardwoods, especially close-grained woods, where oil stains would not be absorbed properly. They should not be used on softwoods.
Varnish stain is a nonpenetrating stain, consisting of aniline dye in a varnish base. It is used by manufacturers to finish drawers, backs, and other hidden parts because it's inexpensive and no further finish is required, but it looks cheap and is generally not recommended for refinishing.
The sealer stains are nonpenetrating mixtures of dye in a varnish, shellac, or lacquer base. Two coats are usually required, and the surface must often be protected with paste wax. No further finishing is required.
Several organic-base stains can be made for use on pine and other woods. The most common organic stain uses tobacco as the color, but stains can also be made from bark, roots, tea, berries, and other natural sources. These stains are interesting, but they're not recommended unless you're an accomplished refinisher.
Using the right staining techniques can save you time and help you avoid messes. We'll review the best ways to mix and apply stain in the next section.