Posts tagged “spirit varnish

The Art and Mystery of Finishing


In centuries past when the master of a shop gave a finish recipe to an apprentice the master knew the secret was safe. Varnish formulas were closely kept secrets of the craft. The apprentice was sworn to secrecy about his craft. The training was all by oral tradition. Those that knew the art of finishing were the varnishers’, stainers’, and painters’. These artisans were organized into guilds in both England and this country.

The first manual on finishing was written in England in 1688 by Stalker and Parker. This “ Treatise of Japanning and Varnishing” was not intended for the artist but for the gentleman that was doing it for a hobby. The first finishing manual in this country was by Jacob Moore in 1827 entitled “The Cabinet-Maker’s Guide” and was advertised to housewives as well as cabinetmakers. It’s interesting to note in reading this some critical steps were left out. The apprentice system had not completely broken down at this time but in another 20 years it was gone. The industrial revolution was the demise of the apprentice system.

The reason to apply a finish to the surface of wood is different today than it was 150 or 200 years ago. At that time what was most sought after was the polished surface that not only enhanced the beauty of the wood but also reflected light. You must remember at that time the only source of lighting was candles or later oil lamps. This is why looking glasses ,or as we say mirrors, were so valued. The more light one could reflect the brighter one’s house would be at night.

Today we apply finish for three reasons. The frist is to keep dirt and grime out of the pores of the wood,to put it another way, sanitation. Wood is also finished for stabilization. This is to slow down the moisture that wood will pick up by the change in humidity. Last is to achieve the sheen, color, and texture we find pleasing: i.e., decoration.

There were four basic finishes available to the 18th and early 19th century cabinetmakers: paint, oil and wax, oil varnish, or spirit varnish.A cabinetmaker could make his own spirit varnish. This was the most common finish used on furniture at the time. Each finish had its strong and weak points to consider.

Painted furniture was very popular at this period. Paint was made with linseed oil, whiting, a dryer, and earth pigments.To this was often added fossil resins such as amber or copal. This made the paint very much like an oil varnish. The colors were very bright and intense with a gloss sheen. Milk paint or “buttermilk paint did not come back into favor until the very early 19th century. One color paint schemes could be done in the cabinet shop but faux finishes such as wood grain or marble were the work of painters. The finish was very durable, moisture resistance, and easy to clean. Unfortunately many of these painted finishes were stripped off in the late 19th and early 20th century

Oil or wax finishes only partly met the requirements needed for a good finish. The oil used was linseed from the flax seed sometime a dryer such as lead was added to speed up the drying. On it’s own linseed drys very slowly and doesn’t fill the pores very well. It does produce a rich color and fair sheen. Bees wax was used as a finish as well. When mixed with turpentine it became soft enough to apply on the furniture and produced a good sheen. The drawback is that it remains too soft on the wood. Both of these finishes attract dust as they slowly dry.

Oil varnish is made with linseed oil, a dryer, and fossil resins. The resins were fossilized tree sap such as amber, copal, and sandarac. It was dangerous to make because of the high temperature that is required to melt the resin. Many a varnish-maker was burned to death when the hot oil burst into flames. It has many good points as a finish. It fills the pores, protects the surface, and adds a richness due to it’s amber color. The  drawback is attracting dust while it drys. Violin varnish could take several months to a year to dry. Work to be varnished was placed under tenting to keep the dust away from the surface while drying. Still occasionally you do find it used as a finish on furniture at this time but rarely.

Spirit varnish is made with shellac and alcohol, thus the name.Shellac comes from an insect secretion of the lac bug in India. It is easy to make, drys very fast, and produces a good moisture barrier. After the finish is built up it gives a very high sheen. It doesn’t hold up well to alcohol or water  spills. It can be made almost impervious to water by the addition of resins. Shellac gained a poor name from furniture of the 1920s’ and 30s’. Often old shellac or metal contaminated shellac was used that caused the finish to quickly degrade. It was the most widely used furniture finish of the 18th and 19th century. In about 1820 when the French started applying spirit varnish with a rag it became known as French Polish. This method of application left no brush marks and produced a higher sheen. Shellac is correct for most period furniture.

 

Unfortunately the vast majority of furniture has lost its original finish due to sunlight, weather ( being set out in sheds), or long ago being refinished. In 27 years of working with furniture I’ve only seen a few pieces that retained their original finish. The majority of these being in museums. Some books that say a certain piece has it’s original finish.  I’ve seen picturers of those same pieces from the 1930s’ in cabinet shops stripped with no finish on them. It is very hard to determine if an antique has an original finish. If you do think about having a piece refinished avoid letting some one use polyurethane or lacquer. The only place I find lacquer applicable is for dining table tops because of food, water, and alcohol spills.