French polisher

French polishing is a wood finishing technique that results in a very high gloss surface, with a deep colour and chatoyancy. French polishing consists of applying many thin coats of shellac dissolved in denatured alcohol using a rubbing pad lubricated with one of a variety of oils (see below). The rubbing pad is made of absorbent cotton or wool cloth wadding inside of a piece of fabric (usually soft cotton cloth) and is commonly referred to as a fad, also called a rubber, tampon, or (Spanish for "rag doll").

French polish is a process, not a material. The main material is shellac, although there are several other shellac-based finishes, not all of which class as French polishing.

The finish is considered by many to be among the most beautiful ways to finish highly figured wood, but it is also recognised to be fragile. It is softer than modern varnishes and lacquers and is particularly sensitive to spills of water or alcohol, which may produce white cloudy marks. However, it is also simpler to repair than a damaged varnish finish, as patch repairs to French polish may be easily blended into an existing finish.

French polishing became prominent in the 18th century. In the Victorian era, French polishing was commonly used on mahogany and other expensive timbers. It was considered the best finish for fine furniture and string instruments such as pianos and guitars. The process was very labour-intensive, and many manufacturers abandoned the technique around 1930, preferring the cheaper and quicker techniques of spray finishing nitrocellulose lacquer and abrasive buffing. In Britain, instead of abrasive buffing, a fad of pullover is used in much the same way as traditional French polishing. This slightly melts the sprayed surface and has the effect of filling the grain and burnishing at the same time to leave a 'French polished' look.

Another reason shellac fell from favour is its tendency to melt under low heat; for example, hot cups can leave marks on it. However, French polish is far more forgiving than any other finish in the sense that, unlike lacquers, it can be easily repaired.

The process is lengthy and very repetitive. There are also many similar variations in schedule and technique. What is described here is one such schedule. The finish is obtained through a specific combination of different rubbing motions (generally circles and figure-eights), waiting for considerable time, building up layers of polish and then spiriting off any streaks left in the surface.

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Wikipedia