Tuesday, January 18, 2011

WILL’S BOW Part 10. Varnishing.

When the stick is completed it needs to be sealed with a varnish. The varnish on a violin is relatively substantial and plays a role in the instrument’s tone. The varnish on a bow, however, can be quite thin since it is only there to seal and protect the wood and prevent the bow from being effected by rapid changes in humidity. Some makers like to apply enough varnish to fill the wood’s pores completely while others prefer the minimum.

The varnish’s main ingredient is lac, the resinous secretion of an order of insects of the Coccoidea family. The insects deposit the lac on the twigs of certain trees in Thailand, India and other parts of Asia. The twigs are collected and thoroughly cleaned to form a deep red granular product called seed lac or the lighter, more refined shellack in flakes. The varnish itself is made by dissolving lac in alcohol and optionally adding small amounts of other resins. The varnish is not applied with a brush but rather with the technique called French polishing where the varnish is applied to a clean cloth with a little oil and rubbed on the bow. A number of coats are applied to bring the bow’s surface to the maker’s satisfaction.

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