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In our continuing series on furniture finishes we turn today to shellac. Shellac was the original clear finish for wood, having originated in the far east centuries ago. Shellac is made by dissolving the dried remains of the lac bug in alcohol. You’ll hear those familiar with shellac refer to one pound and three pound "cuts". This simply refers to the number of po9unds of dry shellac dissolved in a gallon of alcohol. The lower the "cut" the thinner the shellac. Most paint stores offer shellac in pints and quarts in three pound cut only.

Shellac is also available in either clear or amber color. Those of you who remember the knotty pine look in fashion for wood work and cabinets in the 1950's will be interested to know the color was usually obtained by using amber shellac as a wood sealer, and over coating with clear varnish for durability. This brings up two points.

Shellac is an excellent sealer, and can be used under either lacquer or varnish, as well as some polyurethanes (read the label to make certain). Shellac is primarily used today is as a base for stain killers and sealers of various sorts.

Shellac is ordinarily not used today as a finish; it’s too easily damaged. Water will spot it, fruit juices and alcoholic beverages as well as soft drinks, will actually dissolve it. But at one time, it was the finish to use.

Some period furniture, particularly Louis IV, was finished in shellac. Proper care of antiques from that period require that only shellac be used in their finish repair. The term "French Polish" came from the period, as a term used to describe a particular method of applying of shellac. The resulting finish was mirror like, and flawless. Better craftsman today are familiar with the technique and employ it when the quality of the piece demands it, or the customer insists on it. French polishing, which involves going over the surface of a piece of furniture literally inch by inch, applying finish with a small pad is tricky, tedious, and time-consuming, and can not be duplicated by any factory finish I have ever seen.

Application of shellac for finish or sealer is essentially the same as varnish. Work on a small area, don’t over brush, and overlap your work areas as you proceed. Shellac dries considerably faster than varnish, but there’s a caveat here. Shellac sets up by evaporation of the solvent; there is no chemical change as with varnish. When you apply a second coat, the dissolve the first coat, so you must be very careful not to over brush, or you’ll wind up with a mess.

Another bad point about shellac: it is an anhydrous material; that is, it absorbs water. This includes soaking up water from the air itself. If you’re using pure shellac for any purpose I’d make the following suggestions. Buy what you need for the job, no more. Check the date on the can (yes it is dated) and if you can’t read the date, find a clerk who can decipher the code for you. If the product is more than 6 months old, don’t buy it. I don’t keep shellac in my shop after I’ve had it opened for three months, regardless of how tight I reseal the can. Shellac that has absorbed moisture from the air will eventually fail to dry when applied. You’re left with a gummy mess that you have to strip down to bare wood and redo, and you don’t want that.

In today’s world shellac is still an excellent sealer, but a poor choice for finish work.

Next time, a look at oil finishe(s). Until then, if you have question or comments about furnitrue repair and refinishing, drop me a line at the Enterprise.

George Utley has about 20 years experience in furniture
repair/refinishing/manufacturing. His last full-time job in the industry was
as quality control supervisor for a Virginia mfg. producing solid walnut and
cherry period pieces (Queen Anne & Hepplewhite).

George Utley    gtu@buggs.net