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Upon returning from a week at the beach, and while scraping off a week's build up of SPF #10,000 sunscreen, the topic of this month's column hit me like a Boogie-Board thrown by a an eight foot wave: Painting! Which is to say, scraping. In the olden days, long before the Lanham Act, paint was simply a concoction of linseed oil and pigment. Linseed oil is made from pressed flaxseed and is useful as a paint ingredient because it hardens when exposed to oxygen. Another important characteristic of linseed oil is that cattle will walk up to a house which has been freshly painted with a linseed oil-based paint and lick it; flaxseed is for cows, food. While having your house or bathroom licked by cattle does engender a certain charm, that is not the only reason to use such a paint. Not only do cows love linseed oil, but wood treated with linseed oil has a tendency to develop spectacular colonies of mildew. So you could paint your Adirondack chairs with a linseed oil-based paint of any color and watch the chairs slowly turn black. As if that weren't enough, linseed oil has another interesting property: the ability to make things burst spontaneously into flames! Hard to believe, but other binders have been developed in recent years to replace linseed oil. Pigments too have undergone a recent evolution. For centuries the most common pigment was lead carbonate. And while the dangers of lead have been known for centuries, it wasn't banned for use in paint until 1978 when it was replaced with titanium dioxide. Titanium dioxide is vastly superior as a pigment. A single coat of a modern paint containing titanium dioxide covers better than as many as three coats of a lead based paint and discriminating mammals find it even more tasty . Should you choose to avoid cattle-friendly paints containing linseed oil, paints containing synthetic resins called alkyds are a possibility. Alkyd paints dry faster, chalk less, tolerate sunlight better, and are more resistant to mildew than linseed oil-based paints. When people talk about oil paint today what they mean is alkyd paint. Sometime during the Truman administration latex paints were developed. Latex paints, unlike oil-based paints, don't undergo a chemical transformation as they dry. They just dry. Latex paint drys to a strong, thin, flexible film which is thinner than the film formed by an oil-based paint, but it is more durable and deteriorates less rapidly. Early latex paints had problems. They deteriorated in sunlight, turned yellow, and fell off, thus mimicking the symptoms of certain venereal diseases. Over the years these problems with latex paint have been solved and the performance of latex paints has eclipsed that of oil-based paints. Latex paint drys faster, tolerates sunlight better, and is more resistant to mildew than oil-based paints. They also hold their color better, resist blistering, are easier to apply, give off no toxic fumes as they dry, and, probably most important, can be cleaned up with soap and water. One disadvantage of latex paint is that surface preparation is critical. If the surface you're painting is dirty, chalky, or deteriorated, the paint film won't anchor itself to the surface and will soon peel off. Because of this, experts often recommend using oil-based primer, even if the finish coat is going to be latex. The best brushes for oil-based paints are natural or "China" bristle brushes. These brushes are somewhat porous and have split ends so they hold a great deal of paint and lay it down very smoothly. This porousness, however, is a problem for latex paints. A natural bristle brush can pull the water right out of latex paint. Better to use a synthetic brush such as nylon or polyester when painting with latex. The worst part of painting is surface preparation. Loose, peeling paint must be scraped, preferably by someone else, with a (Red Devil brand) scraper, and, if necessary, sanded. Any wall needs to be washed and rinsed. Most paint problems are simply the result of an unclean surface. The best detergent for this is trisodium phosphate (TSP) available at any paint store. If mildew is a problem add a little bleach to the TSP. Putty, wood filler, spackling compound, caulk, and the apartment/dorm room standby, toothpaste can all be used to fill small holes and cracks in walls, but the problem is, these things all shrink and crack as they dry and a second coat has to be applied before painting. The best stuff to use is a lightweight filler such as 3M's Scotchlite Glass Bubbles. These fillers contain very little water and as a result dry almost immediately and they won't shrink. For cleaning up oil based paint on your brushes and other equipment you'll have to use a petroleum distillate based paint thinner or brush cleaner. To get the paint off your body, a mixture of cooking oil and dishwashing detergent will work just fine, and won't irritate your skin; men use gasoline and steel wool; real men of course, use a power belt sander. Painter's tip: when using oil-based paint and you're finished for the day but don't want to wash the brushes only to cover them with paint the next day, just stick the wet brushes in a bucket of water. Next day wipe off the water and start painting. The paint can't dry in the water, and the water and oil won't mix. With latex paint, no problem. Soap and water for everything. Writing about painting is a lot easier than actually doing the work, but while writing this article, I was tempted to locate the painting equipment and start on the outside of the house, although fortunately I located a beer instead.
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