The word Tung is an ancient Chinese term for heart. Today, the term also refers to the large, dark green, heart shaped leaves of the Tung tree. This is a fast growing, deciduous tree that reaches a height of about forty feet when mature. The life span of a Tung tree is about thirty years. Fruit bearing begins in the third year of tree growth.
The Tung fruit occurs in clusters, each of which bear four or five nuts. When the nuts are dried and pressed they yield about twenty percent oil. Under favorable conditions an acre of Tung trees will produce about two tons of nuts and eight hundred pounds (one hundred gallons) of raw Tung Oil annually. Successful cultivation of Tung trees requires exact climatic conditions, including the proper ratio of warm and cool days. The major growing areas include China, Argentina, Paraguay, and parts of Africa.
The first record of Tung Oil appears in the writings of Confucius dated about 400 B.C. . Even then, the Chinese recognized the amazing qualities of Tung Oil. Throughout their history, the Chinese have used Tung Oil to waterproof the masts and sails of junks (boats), to finish furniture of royal families and according to legend, to seal the Great Wall! When Marco Polo returned from China, he brought tales of the wonderful “China Wood Oil”. But Tung oil was unable to capture the attention of the West until this century.
In 1912, the American Ambassador to China shipped Tung trees to California, but they died due to lack of proper growing conditions. Successful Tung plantations were established in the Gulf Coast states during the 1930′s because of the perfect growing conditions. The U. S. automobile industry began using Tung Oil to prevent rust and reduce friction on engine parts. Soon Tung Oil was used to coat the insides of cans, to insulate electric circuits, and to make high-quality paints. In 1969, hurricane Camille destroyed the Tung plantations of the Gulf states and stopped the domestic production of Tung Oil. Even though Tung Oil is now an imported commodity, it remains a vital part of American industry.
TUNG OIL VERSUS OTHER FINISHES
In recent years, those who appreciate the warm richness of beautiful wood have begun to realize what the ancient Chinese knew; when turned into a finishing product, Tung Oil is the finest natural wood finish in existence and has yet to be duplicated synthetically!
Man’s ingenuity has created many synthetic finishes, including lacquer, shellac, and varnish all of which protect wood with a hard impervious layer. But these surface finishes prevent the development of patina, the lovely depth and tone that only natural aging can produce. Eventually synthetic finishes will break down and discolor, when that happens the entire surface must be removed by labor intensive stripping and sanding before another coat is applied.
Penetrating finishes formulated with linseed, soy or paraffin oils actually go into the wood and enhance its natural beauty, but these oils often dry incompletely and fail to form a hard and durable surface. Furthermore, they develop a gummy build-up when additional coats are applied. Linseed oil, the most commonly used penetrating finish, darkens and changes color with time and finally disintegrates.
A Polymerized Tung Oil finish is hard yet flexible, waterproof and impervious to alcohol and many food acids. Polymerized Tung oil as a penetrating oil allows wood to continue its aging process and to develop its patina. The wood’s rich color and grain are enhanced by the natural ambering (coloring) of Polymerized Tung oil over time. Any sign of wear disappears when a thin “maintenance” coat of oil is rubbed in. The maintenance coats, rather than cause a build-up, actually improve the patina as they protect and preserve the wood. A floor, a piece of furniture, or any other wood object finished and maintained with Polymerized Tung Oil will never have to be stripped again. The finish will become more beautiful with time.