During my stay at the Marc Adams School, I had a chance to refresh my French polishing skills. Today, French polishing has become synonymous with a high-gloss finish. To woodworkers, however, this term is specific to a technique for the application of shellac. Shellac is a natural product derived from insects that range in Southeast Asia. It is collected, and processed to remove the sticks, leaves, and other “foreign matter”.
Next, it’s ground into coarse particles, and separated into various colors…
Further processing leads to it in the familiar “flake” form with which woodworkers are familiar…
This is an over-simplification of the procedure. The interested reader is referred to Vijay Velji’s article, “Shellac’s Amazing Journey” in Fine Woodworking number 215.
When I first learned French polishing, the process began with pore filling using linseed oil and pumice. Patrick Edwards, however, omitted the oil simply applying the pumice with the pad moistened with alchol. His experience has shown that once the oil has evaporated through the shellac, as the piece ages, the accumulated pumice powder shows through. The alcohol dries well before the shellac is applied, and so the excess powder can be easily removed. This technique has the added advantage of burnishing the surface to a glossy shine, almost evident in this photo…
This result was achieved with under an hour of effort to facilitate the seminar. However, when properly executed over the course of several days, you can understand how the surface will shine. Once, and only once this treatment is complete, can the finisher begin the shellac applications. Keep in mind that French polishing is a slow process requiring patience, and persistence. It is not meant to be rushed, and usually occurs over a period of several days to weeks.
So why do woodworkers torture themselves with this process in this “modern” day? For several reasons:
• French polishing can be performed with simple, inexpensive materials – it’s just alcohol, oil, shellac, and cloth! No fancy spray guns, or figuring out which brush type to use!
• Shellac is an easily repairable medium. Many times affected pieces can be treated on site whereas other finishes necessitate having to haul the damaged piece back to the finisher’s shop. That’s an added expense!
• Finally, as I mentioned before, shellac and its solvent, alcohol, are natural products. They’ve been used for over a century with few to no ill-health effects. In fact, shellac is one of the few “finish” materials that is an FDA approved ingredient in medicines and food products! Ever wonder how the produce in your local grocery got its shine? It has been coated with shellac!