Wood Finishing: Shellac Supply Improves

For shellac finish users, good news: Shellac flakes have become more plentiful. Even those familiar with shellac may not know that it starts out as a crusty protective coating secreted on tree branches by the tiny lac bug (Laccifer lacca), which infests certain trees in India, China, Thailand, and to a lesser extent, Mexico. The coated branches are harvested, and the seedlac is scraped off and processed. After experiencing several years of weather-related shortages of lac bug secretions, supplies are making a comeback, says Steve Krohmer, VP product marketing at Rockler, the woodshop tools and suppliers marketer. Rockler sells Liberon Shellac Flakes. Liberon is based in France, where it does business through the V33 Group. Liberon brands of pastes, waxes, paints, tints, lacquers and other finishes are used to restore furniture or to replicate classic finishes on contemporary wood projects. In the U.S., the master distributor for Liberon is Seppleaf, which sells through numerous local dealers, as well as other big regional retailers like Woodcraft. Seppleaf has posted many technical sheets on shellac, including dragon’s blood and gamboge methods for tinting the coating material. Rockler has been promoting the improved availability and the addition of three new varieties of Liberon Shellac Flakes to its selection of finishing products. “Shellac flakes have been hard to come by in recent years,” says Rockler’s Krohmer. “We are excited about the current upswing in production. It allows us to increase the availability of this versatile finish.” Rockler offers the Liberon Shellac Flakes in Garnet, Lemon and Blonde Dewaxed varieties, in 250-gram packs. Typically, the flakes are dissolved for 24 hours in methylated spirits and then brushed or sprayed onto wood surfaces for a durable, high-gloss finish. The adaptability and warm, rich look of shellac – fast-drying, easily repairable, non-toxic and even approved for toys – makes it highly prized. Rockler explains the production and application of the seedlac: Raw seedlac naturally contains dyes, some of which are removed as the material is washed. But some dyes remain, and their color varies with the type of tree, geographical area or even the time of year when the seedlac is harvested. These variations produce the different colors of shellac. Raw seedlac also contains wax and bits of bark, twig wood and insect remains left over from scraping. To remove these impurities, the seedlac is melted or dissolved in alcohol and strained. It might then be filtered to lighten its color or undergo a process to remove the wax. The purified resin is dripped onto a sheet to cool into “buttons” or is stretched or rolled into sheets, which dry and are broken into flakes. This wax-free “dewaxed” shellac works well for sealing stains, odors and knots, and can be used under other finishes. Since users dissolve shellac flakes in de-natured alcohol, you also clean your shellac brush with de-natured alcohol, the only solvent that dissolves shellac. Also, shellac that is sold as a liquid in a can has a shelf life. “As the product ages in the can, it loses its quick dry/quick sanding abilities,” says finishing expert Bernie Bottens. Beware of the date stamp on the can when you buy it.

Math For Wood Finishers

Whether mixing wood finishing recipes for a post-cat or enlarging a wipe stain recipe, we need to be able to understand and use proportion to correctly do that.