By Michael Good | SDUN Columnist

People working in the building trades have colorful imaginations, to put it politely. Provide a topic (nail guns, for example), a victim (itinerate non-English-speaking worker from a far-off land), add a social lubricant (beer!), then stand back and listen—the lies will fly faster than fasteners from an out-of-control Senco nailer. As many a prophet has learned, it’s hard to compete against the bright and shining lie, especially when it’s being colorfully told by a dusty guy in a hardhat. Nevertheless, like Moses in the wilderness, I offer this list of the top five wood whoppers.

1. SORRY, WHAT YOU HAVE THERE IS PAINT GRADE WOOD

When your house was born, they graded roads, they graded report cards, they even graded wood, but they didn’t designate one species “stain grade” and another “paint grade.” With very few exceptions, all houses built before 1940 were trimmed—in every room—with what we would today call “stain grade” wood.

Pre-World War I and II housing was built with clear, old-growth heartwood, meaning the lumber was free of knots and came from the center of the tree, which is dry and dense and hundreds of years old. In the early days of logging, the sapwood, cambium layer and bark were discarded, leaving the heartwood for baseboards, casings, doors, china cabinets, bookcases, mantels and so on. The wood used in framing was usually also heartwood, though it may have had some knots.

The popular misconception about the quality of wood used in painted trim, and therefore the advisability of stripping it, or even keeping it, comes from the assumption that Douglas fir is not worth staining. In San Diego, Douglas fir was the principal trim material in most formal rooms built between 1900 and 1915. It is the quintessential arts-and-crafts wood trim. Fir fell out of fashion because of fashion, not because of anything intrinsically wrong with the wood.

Once hardwoods became popular for clear trim in the 1920s, builders continued to use finish-quality Douglas fir in the back of the house. There were practical as well as financial reasons for this: Fir was softer and easier on tools (and most trim carpentry was done with hand tools, including chisels). It was readily available. Lumberyards in San Diego were always stocked with it, so work delays because someone hadn’t ordered enough trim weren’t a problem. Builders put up houses quickly (in three weeks) and built several at a time, so using the most plentiful wood just made sense.

Today, Old Growth Douglas fir is more expensive than tropical hardwood. If you have it, maintain it. Like an antique, it’s getting more valuable every day.

2. DON’T WORRY: WE ONLY USE THAT SAFE STRIPPER

You won’t find safe stripper at Home Depot for the same reason you won’t find a “safe” hammer. In order to be effective, strippers (and hammers) have to be strong enough to hurt people. Both methyl chloride and N-methyl pyrrolidone, the two active ingredients in most paint strippers, pose health risks. Products using pyrrolidone can claim to be safer because methyl chloride has been found to cause cancer in one particular strain of lab mice (but not in people). Stripper—like most adhesives, finishes, solvents and, well, just about everything used in construction—is bad for you. Wear protection!

3. GUMWOOD IS EUCALYPTUS

Though we’ve covered this subject before, apparently not enough of the 30,000 or so people who faithfully read Uptown News got the message, told their friends, jumped on the Internet and created the sort of viral sensation necessary to squash this widely held myth. The fact that Eucalyptus had been planted for lumber in Southern California, plus the fact that in Australia they are called “gum trees,” combined long ago in the popular mind to form the now ubiquitous assumption that there is some connection between the trees that grow in our canyons and the wood that graces our china cabinets. Actually, the source for gumwood can be found even closer to home. It is Liquidambar styraciflua, a popular San Diego street tree that often grows right in front of gumwood-trimmed houses. Although much loved in San Diego, gumwood is reviled in the South, where it grows wild. In the 1920s, an association of Southern lumber producers started marketing Red gum, or Gumwood as they decided to call it, to Southern California homeowners and builders. Their loss was our gain.

4. JUST A LITTLE LIGHT SANDING, AND WE’LL BE DONE

Wood refinishers love to sand. It creates a lot of dust, makes a lot of noise and creates the illusion that you’re really doing something important. But sanding removes the oxidized layer that gives old wood that old-wood patina. It makes something old look brand new, which is not the goal. It’s also a lousy way to strip wood. It’s more likely to liquefy the paint and force it back into the grain of the wood than it is to remove it. You have to sand away the wood to remove the paint. And destroying the wood is also not the goal.

But sometimes sanding can’t be avoided. Particularly when wood is damaged, either by exposure to water, sunlight or angry people with power tools (sanders, for example).

5. THE STRIPPER BURNED DOWN THE HOUSE

This sounds like a Charlie Sheen tabloid headline, but it’s actually an abbreviated version of a recent article in a local newspaper (not this one), which blamed a house fire on “stripping materials.” Paint stripper isn’t flammable. Many other materials used in refinishing are, however. Lacquer thinner is highly flammable. It won’t just burn down the house, it will blow it up as well. Rags soaked in linseed oil (which is used in stain and varnish) can spontaneously combust. Alcohol will burn, as will mineral spirits. Even sawdust can spontaneously ignite. But methyl chloride stripper, despite what you may have read, doesn’t cause fires. (It just feels like you’re on fire when you get it on your skin.) Wear protection!

If you seek further enlightenment on the subject, read Bob Flexner’s “Understanding Wood Refinishing.” Then read it again. For in-person wood advice, or to swap colorful stories, contact me at housecallssdun@gmail.com.

MORE FINISHING FIBS:

In addition to the five fallacies, here are some smaller sins to consider:

“We do it just like they did in the old days.” Well, if you do, then you’re an idiot. Finishes today are superior to those of 100 years ago. Why not use them? (The exception is shellac made from flakes, which is authentic and performs well in most situations.)

“We make this stuff up in our shop.” And you, sir, are a nincompoop. Unless you’re a chemist, with a well-outfitted lab, then you’re still a little strange.

“I have this trick I learned.” There isn’t one trick to wood refinishing. There aren’t even 10 tricks. There are an endless variety of problems to solve based on knowledge, skill and a willingness to keep trying.

“I learned this in the old country.” There are no handed-down-through-the-ages trade secrets in wood refinishing. All that’s required is the ability to read. Again, you can’t go wrong with Bob Flexner’s “Understanding Wood Refinishing.” When your project doesn’t turn out the way you planned, it’s usually something you’ve done, not something to do with your ancestry.

“We’re very economical.” There’s nothing cheap, fast or reasonable about restoring your woodwork—not if you do it right, that is. It takes time. And time is money. The alternative—doing it on the cheap— isn’t very economical either, because you risk destroying your valuable investment.

“This will last the life of the house.” Nothing lasts the life of a Redwood house, certainly not varnish. The life of a clear finish should be measured in dog years, not tree years. If your finish has lasted more than a decade, throw it a birthday party, then clean it and recoat. After all these years, it deserves it.