Purfling is decorative inlay. On violins it is the little black and white line that runs around the edge of the top and the back. Purfling is made from three pieces of wood sandwiched together to make a black-white-black pattern. A very small channel is cut parallel to the edge of the instrument and the purfling is glued into this.
Materials for purfling vary widely among makers and can be a useful way to identify older instruments. Stradivari, and most everyone in Cremona, used pearwood that was dyed black for the two outer strips and poplar for the white center strip. German makers tended to use maple for both black and white. Some French makers used ebony for the blacks, as it does not need any dying, but ebony is notoriously brittle and hard to bend into shape. Sometimes materials other than wood were used, such as the Testore family, who apparently used corn husks or some kind of paper, or the Dutch school of violin makers who used whale baleen. One Roman maker even used silver for his “blacks”.
I make my purfling with pearwood and poplar. The traditional way to make purfling is by making one large plane shaving off the edge of a board. With this method I can get a very consistent shaving thickness or I can vary the thickness slightly. It depends on the maker’s style I am trying to copy. Getting the thicker shavings needed for cello purfling is a lot of work for one person. At Oberlin we experimented with having several people on one plane-one on the front pulling with a rope, one steering in the middle and one pushing from the back.
I dye the pearwood black with Logwood, Haematoxylum campechianum, using a traditional recipe. The Logwood actually dyes the shavings a very deep purple. After soaking in the Logwood solution, I lock in the color and turn them black with a small amount of ferrous sulphate, a chemical used for centuries in ink manufacture.
After gluing the shavings together between two boards, I cut 3mm strips from the side of the “sandwich”. These are the strips I will turn on their side and inlay into the instrument’s edge.
Purlfing highlights the outline of the instrument and adds style to the corners. Each maker handles how the purfling is inlaid slightly differently.