Varnish

achievc a high gloss. (See sidebar on page 40.) Outdoors. varnishes needed to be more elastic to survive greater wood movement, so outdoor varnishes contained a higher percentage of oil and were called "long oil" or "spar" varnish. Some of these natural-resin varnishes are still available, especially spar varnish.

In most varnish today, the natural resins of old have been replaced with synthetic alkyd or phenolic resins. Phenolics tend to be harder and more durable, which make them the best choice for projects that are to be rubbed to a high gloss, or used outdoors. But phenolics are more expensive and tend to yellow more than aikyds, so alkyd varnish is more popular.

Polyurethanc is another synthetic resin-type varnish. Polyurethanes are formulated in different ways for different uses. Some types cure by contact with moisture or heat. Some are two-part finishes that cure by chemical reaction when the parts are mixed. These types of polyurcthane are used mostly by industrial and commercial finishers. They're tricky to work with and virtually impossible to repair or remove with chemical removers.

The polyurethane we buy at the hardware store is a more user-friendly blend of polyurethane and alkyd resins, sometimes called uralkyd. This uralkyd polyurethane is tougher and more resistant to heat and solvents than conventional alkyd varnish, but it has some drawbacks. It does not adhere well over other finishes, or on some stains and paste fillers. Polyurethanc is difficult to repair, difficult to strip, difficult to rub out (due to its elasticity) and has a difficult-to-describe plastic look. But polyurethane is very popular, because consumers accept these difficulties in return for polyurethane's durability.

So when should you choose polyurethane over alkyd varnish? Polyurethane is appropriate when toughness is a prime consideration. For example, a bar top that sees heavy wear-and-tear is a sensible candidate for polyurethane. For furniture that won't be exposed to physical abuse, alkyd varnish or phenolic varnish— rubbed to a beautiful satin or gloss—is a more appropriate choice.

All of these varnishes are solvent based, that is, they are thinned with hydrocarbon solvents. Recently, we've become aware of the toxicity of these solvents— they're bad for our health and our atmosphere. So there's a great push in industry to replace solvent-based varnishes with water-based formulas. Some have already appeared on the market. I don't think they equal the solvent-based varnishes for toughness, ease of application, and especially appearance, but it's an area to watch for rapid change in the near future.

Varnish can be bought in a number of sheens, from gloss to dead flat. Flat formulas contain finely powdered silica. The silica settles to the bottom of the can and needs to be stirred before using. Stir varnish slowly, and avoid using a whipping motion,which could result in bubbles, which pop during the oxidation process, leaving small pin holes in your finish.

Instead of dipping my brush into the varnish can, I transfer the varnish into a wide-mouth quart jar or plastic container, which I fill only '/i to xh full. I like to tap the brush against the side to remove excess var-

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Transfer varnish into a wide-mouth quart jar or plastic container filed 7i full. To avoid getting air bubbles in the varnish, remove excess varnish by tapping the brush against the side of the container instead of wiping the brush against the Hp.

When brushing varnish, begin sightly in from the edges, and brush bach toward them to avoid runs down the sides. Then, vrork in towards the center and across the surface. After covering the entire surface, "tip off" by brushing very lightly, holding the brush at a 75 angle and brushing from side to side with the grain.

Transfer varnish into a wide-mouth quart jar or plastic container filed 7i full. To avoid getting air bubbles in the varnish, remove excess varnish by tapping the brush against the side of the container instead of wiping the brush against the Hp.

ois Varnish

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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