Tuesday, June 12, 2012

French polishing...

I tend to use hand tools in my studio for the most part. Hand tools, when used effectively, impart a finish on woods which bring out the natural lustre of the surface. With this in mind, I should really carry this philosophy over to the finishing component of my work. I like to use hand-applied finishes for finishing. There are a few reasons for this and health and safety concerns are high up on the list. The main reason however is the clarity and depth that hand-applied finishes provide. My favourite film finish is shellac. You can't get a more natural film finish than shellac since it is derived from the lac bug and not man-made. Applying shellac however is altogether an art in itself. Shellac has been used as a finish for hundreds of years and only in the early 20th century was it replaced with modern day commercial type finishes. Modern spray finishes were developed to speed the finishing process.

The traditional method of applying shellac is to use the French Polish method. This involves laying down hundreds of micro thin coats of shellac using considerable elbow grease. The micro thin coats are gradually built up , then levelled and finally a process called polishing is used to acquire the mirror finish which French Polished finishes are known for. I've been quite intrigued by how this technique has remained the same over the centuries. It is a technique that was originally developed for musical instruments because the thinner, somewhat flexible finish aids in the accurate transmission of sound. Shellac finishes also bring out the depth and color of woods in a way that other film finishes do not. Other film finishes tend to obscure the underlying wood because they usually have a high amount of solids in them. The high amount of solids aids build up a finish quickly, something not necessary when hand applying shellac using the French Polish process. The French Polish process can take days to complete as it involves multiple sessions and the curing times in between so you need to have patience with this.

I don't use this process in all my work, but when I am using special woods in a piece I am creating; this clarity and deep finish is well justified. In the photo above, I am half-way through a French Polishing session and snapped this cool photo showing the already highly reflective properties of the finish.