SECRETS OF PAINT AND STAIN CHEMISTRY

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The phenolic (phenolitic) resins used in advanced paints and varnishes are derived from the carcinogen benzene plus phenol—a tech term for carbolic acid, which will eat the enamel off your teeth. Thankfully, the components are rendered harmless when mixed into a 1-part finish in the plant.

You can find a limited number of clear polyurethane finishes with water as a base. They are surely the future—they're hard and won't yellow as quickly as most varnishes, and the nonflammable solvent is nearly odorless. Today's water-base poly finishes are vulnerable to water damage however, so are suitable only for interior use. Fifty-year established West Coast manufacturer WOOD-KOTE makes Cascade-Poly-Kote that is worth investigating.

Two-part finishes are fluid versions of the familiar epoxy/amine-resin "5-minute Epoxy" adhesive or the resins used to encapsulate fiberglass in boats, bathtubs, and auto bodies. The two components are mixed on the job from a resin and a hardener that combine into a stable solid. The volatiles released are harmless enough that no warning is given on the containers (it smells like vinegar—dilute acetic acid, chemically: CH3COOH and is used industrially to make plastics and rubber). The cured epoxy is totally inert, and the process of making it releases only vinegar and heat into the environment. The process combines two (or more) possibly toxic precursors to produce benign endproducts that are true wonders of modern chemistry, able to outlast their lo-tech and intermediate-tech predecessors by many times.

For now, though I think picking and choosing to find the paint technologies most appropriate for my needs. I'll stick to lo-tech natural ingredients to make my own stains, putties, and sealers, shellac, varnish, and paint for old-time woodworking projects. For elegant furniture made from fine woods, I'll rely on modern namebrand penetrating oils and varnishes made with ingredients that aren't available on the farm. I'll continue painting the old barn with traditional paints, but will apply major-brand latex inside the house. But I'll rely on properlyequipped pros to apply house exterior, auto or boat finishes incorporating the latest in sophisticated technology.

APPLYING A VARNISH FINISH

The point of using varnish is to get a hard, wear- and weather-resistant finish that is clear so the wood grain and color show through. It can also be made as smooth as a sheet of glass. The latter is not a particularly practical objective, but a noble and virtuous undertaking just the same. In pioneer homesteading days, the first crop went into a solid barn roof. But, once the second crop was in, a pioneer woman wanted a varnished dining table she could polish with beeswax and see her reflection in—even if the house was still built from logs with a dirt floor. That fine finish was proof that beauty still existed, even in her hard-scrabble life.

Can't blame her. From my perspective three centuries later, the result of 40 hand-brushed coats of clear spar varnish on the well-faired African mahogany shanks of a 1939 Chris-Craft barrrel-back runabout, or 20 coats of cherry red acrylic lacquer sprayed and buffed out on a 1970 Camaro SS is flat-out, drop-dead gorgeous.

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