Why wax wood?

The primary reason you apply a finish to wood is to seal and stabilize it. That is, you try to slow down its absorption and release of moisture, normally in the form of water vapor. If you don't, the wood will dimensionally change as it swells and shrinks, resulting in splits, checks, cracks, loosened joints, and other movement. That's why experienced woodworkers always put the same number of coats on all exposed parts of the wood. If a tabletop gets three finish coats, so does its underside. When that's accomplished, though, and the furniture goes in service, other attackers take over. ( See "The finish killers," below.)

The easiest added protection you can provide—at least against the accumulated effect of small scratches and abrasions—is a coat of wax. Wax provides a slick surface film that reduces traction of cups and other items coming in contact with it. It also fills the microscopic dents and other crevices in the surface that catch and hold light. This means light reflects better off wax, giving the finish added shine and a richer appearance.

At one time beeswax (taken from bee hives) was the only wax available. Today, though, manufacturers employ it as well as paraffin (from petroleum), carnauba (from palm tree leaves), and synthetic waxes in blends for their commercial paste waxes. That's because each of the natural waxes has its own characteristics. Beeswax rates as medium-soft in hardness, easy to apply as polish, and results in a low semigloss appearance. Its melting point is about 150°.

Carnauba is a very hard wax and produces a higher sheen than beeswax, but when used alone, it's very difficult to buff out. It melts at about 180°.

Paraffin is even softer than beeswax and has a lower sheen. It melts at 130°, and is never used alone for polishing because it just doesn't do the job.

Manufacturers try to blend these waxes to arrive at a paste that's user-friendly, but that also produces a pleasing, protective gloss when buffed. About the only difference between brands comes from the amount of each type of wax used and the solvent that turns solid wax into paste. The latter results in different drying times—the length of time you wait before wiping off the excess.

Liquid furniture polishes come primarily from solvents of distilled petroleum. That's why they're oily. Manufacturers add a fragrance to douse the petroleum smell. Liquid polishes of this ilk add the same shine as paste waxes, yet it lasts only until the polish evaporates. And that could be in a few days.

Some liquid polishes do contain small amounts of wax or silicone oil, and sometimes both. When they do, they can perform almost as equally as paste wax. However, silicone polishes can pose refinishing problems. Penetrating into wood through finish nicks and cracks, silicone prevents reapplied finishes from flowing properly. All in all, though, most liquid polishes act better as furniture cleaners than as protectors.

Note here that if a wax lists toluene on the can as the solvent, don't use it on a water-based finish or damage will result. And remember that the solvent in all waxes can dissolve any finish if it hasn't cured completely. Too, forget about "wax buildup." If properly applied, there won't be any because you remove about 99% of it in the buffing. What does build up is the protection, and it's clear.

Applying paste wax isn't a cinch, but it's not a real chore either. And you should only have to do it every six months or less. Before you start, make sure the furniture is clean. If it looks dirty, clean it with a damp cloth and a mild soap (Murphy's Oil Soap or Ivory). Then dry the surface.

To apply, plop a marble-size blob of wax in the center of a soft, lint-free cotton cloth (part of an old diaper or T-shirt is good). Fold the cloth around the wax. If the wax feels hard, roll it around in your hands to soften it. What you want is to have the wax ooze through the cloth, dispensing just a little bit onto the surface as you wipe. (To level out and dull a glossy finish, apply paste wax with 0000 steel wool. Put it on with the grain to keep scratches from showing too much.)

Wipe in any direction on the surface to spread the wax. When it's completely covered, wait for the solvent to evaporate (the wax will turn hazy). Then, with a fresh piece of lint-free cotton cloth, begin wiping off the excess.

When you can no longer make a smear in the wax with your finger, the excess has been removed.

Now buff the wax with another clean, lint-free cotton cloth. The softer the cloth, the higher the sheen you'll achieve. (You can opt for a lamb's-wool pad in your power drill.)

When you've finished buffing, repeat the waxing process. Like spraying on a finish, it's best to apply two or more thin coats than one thick one. The second coat also covers any spots that you may have missed in the first application.

For maintenance, all that's necessary is an occasional dusting and wiping down with a damp cloth. You can rebuff, too. However, never apply liquid furniture polish atop a finish that's been paste-waxed. The solvent in the liquid polish will dissolve the wax.

In addition to the constant fight against moisture, a furniture finish also must ward off the following threats:

* Too much light. Bright sunlight is the main culprit—its ultraviolet (UV) rays darken the wood through the finish. Indoor light, though less intense, also contributes to finish deterioration.
* Oxidation. Oxygen in the air eventually breaks down a finish into its components, making the wood beneath vulnerable. Although slow, oxidation causes a finish to darken and crack, even in the absence of light.
* Acids, alkalis, heat, solvents, and water. Excessive contact with any and all of these mars and damages a finish.
* Everyday use. Tiny abrasions and scratches accumulate to dull and wear down a finish.

Of course, you have finish-preservation strategies for each of the above. You can keep furniture away from bright light and cover it when you go on vacation. Finishes with UV fighters help, too, but they're normally formulated for outdoor use. Heat accelerates oxidation, so don't store furniture where it's hot or place it near heaters. Coasters, hot pads, and tablecloths guard against heat and spills.

Here's a sampling of the paste waxes you'll find at woodworking suppliers and hardware stores:
Antiquax, Black Bison, Briwax, Butcher's Wax, Johnson Paste Wax, Minwax Finishing Wax, Renaissance Wax, and Treewax.