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The Dirt on Clear Coat Finishes

spray lacquerClear-coat finishes aren’t as clear as they used to be. In the good old days, the choice was lacquer, shellac (French polish), or poly-thane — things with a little bit of variety in sheen, and yellowing or non-yellowing mixed in. That was it, the universe of options.

Lacquers’ Origin: Lacquer is just a Sanskrit word for “wax.” As a result there are more than one type of finish called “Lacquer.” One originates with the lac insect and was used as a wax type of finish product. The other is a secretion from a lacquer tree that was first used around 1600 BC. Both types were used as a coating of choice for artisans on pottery, wood and even furniture. Regardless of the origin, it was abundant, dried relatively hard and could be polished.

It could also be colored with pigment and used as paint. During the 30’s the automobile industry created a solvent-based lacquer most of us still use today. It was easily sprayed on wet, dried fast and could be polished to a beautiful mirror-like finish. Another reason artisans love to use lacquer is that after it dries it can be re-coated if scratched. This is possible because lacquer melts into each coat and forms a chemical bond. This is highly desirable because a finisher can shoot many coats in a few hours, saving time and making that cabinet or item of furniture look beautiful.

This technique of layering lacquer coats made it possible for to “buff” out the softer lacquer using compounds and wet sanding to produce a “mirror” or “piano” finish. It has been said that when an item is completed with a buffed out, lacquer mirror type finish, you can hold a tape measure vertically to the table top, look down into the top and actually see the tape measure and read the inches in the mirror image. Some of the best work makes it possible to read 36 inches down into the buffed tabletop.

Lacquers let the wood expand and contract without cracking, and whether clear or pigmented, can easily be repaired for scratches and refinishing. This is why most manufacturers love to use it. You can also pick your sheen from a matte, waxy finish to high gloss.

The only con is that a lacquer finish is soft and can easily be scratched; but it can also be easily repaired.

Today, there are catalyzed lacquers that are harder and used for tabletops in commercial applications. There are also water-based lacquers that are excellent and used for all of the above. The advantage of modern lacquers is safety factor for the craftsman; they’ are much safer than some of the old formulations. Lacquer is our go-to finish because of ease of use and speed by which we can deliver a product.

Polyurethane somethings: These finishes are designed to be extra hard and used in areas with high use or have the potential for wear such as in flooring or commercial purposes – bar tops for example. They dry much harder and are pretty much resistant to environmental hazards like sun, scratches, and abrasion. When used on wood they can offer very effective protection. But, as with anything, there are trade offs. Polyurethanes have a much longer drying time. They also form a mechanical, not a chemical, bond, meaning that if multiple coats are necessary, the undercoat must be properly prepared and sanded to accept the next coat.  This is extremely time consuming — not cost effective.

Polyurethanes used on soft woods will crack and peel due to expansion and contraction of the wood. It is possible to effectively use polyurethanes and even 2-part epoxy urethanes on metal, medium density fiberboard and hardwoods. Use thin layered coats and make sure the surfaces (substrates) are lightly sanded as poly’s make a mechanical bond. Once dry polys can be buffed out for that perfect high gloss mirror finish. They will look spectacular, almost as if they were still wet — but it’s a lot of work! Also due to the moisture content of wood you will need to totally encapsulate the entire door, wood table top, etc., so that the expansion and contraction due to the moisture content changing will be uniform on the entire surface of the coated material. A good craftsperson will coat underneath a table as well as on top. This makes for a smooth under side and is a tell tale sign your wood worker knows what he or she is doing

Take away: The indoor choice for furniture and cabinetry should be your craftsperson’s choice based on its primary use. If it needs extra durability then catalyzed (extra hardened) lacquer is best. If the wood needs extra protection, then polyurethane will be the best choice. Ultimately, your best option is to work with a skilled and experienced craftsperson who can help you achieve your vision — aesthetically, functionally, and most of all, economically.


gerryGerry Lamanski is an internationally known professional woodworker, cabinetmaker, inventor holding numerous patents and artist. In his 30 years in the design community he has designed and built residential, commercial and hotel furniture and fixtures. His most unique projects included a secret, hidden room in a Southwest art collector’s office, professional magician’s props and the interior of Willie Nelson’s private tour bus. Renowned for his Arizona Ranch Style designs he was named one of Phoenix Home and Garden’s “Master of the Southwest” for 2014. Working from his studio in Tempe, Arizona, Gerry continues to delight and surprise the design community with his innovative and timeless designs. In his spare time he serves on an advisory committee for a non profit helping veterans and fosters for a local dog rescue group. Should you have a challenging project you can reach him through his website www.arizonaranch.com.

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