Wood of the Month:
Dramatic Cocobolo Yields Valuable Veneer

By Jo-Ann Kaiser


FAMILY NAMES
Dalbergia retusa of the Family Leguminosae

OTHER NAMES
Cocobolo, granadillo, grenadillo, nambar, funera, palo negro, cocobolo prieto

HEIGHT/WEIGHT
The average height for trees is from 45 to 60 feet with trunk diameters of 20 to 24 inches. Weight ranges from 61 to 75 pounds per cubic foot with an average weight of 68 pounds per cubic foot. Specific gravity is 1.10.

PROPERTIES
Cocobolo is a very heavy, tough and strong wood. It rates high for strength but is rarely used for that purpose, although the wood is used to make small tool handles. The wood dries slowly. Opinions about drying are mixed. Some say the wood has a tendency to split and check and others say the wood has excellent drying properties, free of surface and end checking. A T1-B1 kiln schedule is recommended by experts. Another expert recommends seasoning the wood in log form. The wood has low shrinkage with high stability in use and very low moisture absorption. It is not considered difficult to work with either hand or machine tools, but sharp cutting edges are recommended. Screw and nail joints hold well. Pre-drilling is recommended. The wood finishes well with normal care but the wood darkens quickly and some experts recommend the use of UV-resistant varnishes.

In Mexico, the tree is called granadillo, but in most places around the world, Dalbergia retusa is known as cocobolo. Cocobolo timber is sturdy and yields some very interesting, beautiful figures. The wood is usually cut into veneers for use in inlay work and fine furniture.

Related to Rosewoods
The Encyclopedia of Wood, includes information about cocobolo and describes its relation to other members of the dalbergia family. "Collectively rosewood denotes various species of dalbergia; in particular Rio or Brazil rosewood, Indian or Bombay rosewood, and Chinese huang-hua-li. Close cousins include tulipwood, kingwood, and cocobolo, the diverse colors of all of which were used in the elaborate marquetry decoration of the furniture and joinery of the 18th-century Europe. The wood is seldom seen in the solid, except in oriental furniture."

Cocobolo can be found in the Pacific regions of Central America, extending from Panama to southwestern Mexico. The trees grow best in the drier uplands and tend to be small in stature. Cocobolo is usually shipped from growing areas like Costa Rica and Nicaragua in small, round billets. It is most often available in turning blanks or veneer.

The sapwood of cocobolo is so pale it is almost white, but the heartwood is a mix of brilliant colors ranging from deep reds to an attractive mix of streaks and markings of red, black, purple, yellow and orange.

World Timbers of North and South America describes the dramatic palette of cocobolo as "considerably denser than Brazilian rosewood. The color is remarkably variable; the bright hues of the freshly cut wood tone down to a deep-red, streaked or mottled with black."

Cocobolo's grain can be straight, but it is also sometimes irregular and wavy. The wood has a fine, medium texture.

Good Looks Matched by Toughness
Cocobolo is more than just another pretty face. The wood is heavy, strong, durable and resistant to preservative treatments. Its uses include architectural woodwork, turnery, tool handles, musical and scientific instruments and specialty items such as steering wheels, buttons, canes, wooden jewelry, jewelry boxes, chess pieces, and brush backs. Cocobolo is also very popular for use as cutlery handles.

Cocobolo contains natural oils that allow the wood to be polished to a finish resembling marble. Veneers, A Fritz Kohl Handbook describes cocobolo as "an absolutely superior wood. Due to its high oil content the surface appears dense with waxy luster."

Constantine Jr., writes that "if the smooth surface is rubbed with a cloth it will acquire a waxy finish without the use of any oil, wax, shellac or filler. Lengthy immersions in soapy water have little effect on the wood except for a slight darkening in color."

Beware of Wood Dust

Although cocobolo is a fine turning wood and most consider it easy to work with, sanding and machining the wood produces a fine dust that can cause dermatitis or a poison ivy-like rash. The dust can also cause orange stains when it comes into contact with skin.

Boston-area custom woodworker Eric Englander agrees that the wood's dust can be problematic. "People I know who use it wear a mask, gloves and long sleeves when they are working with it," he says.

Albert Constantine Jr., in Know Your Woods, expresses similar concerns about cocobolo's dust. "When working with cocobolo," he writes, "care must be taken to protect oneself from the fine dust, as it produces a poisoning similar to ivy poisoning. It can become very painful. When affected, a person usually has to remain away from work for a week and then may never again be able to be in a room where there is any cocobolo dust."

                                                                                                                                                                                           

Have something to say? Share your thoughts with us in the comments below.