Balsa

Balsa is the lightest, softest wood used commercially. The lightwood balsa is really a hardwood, though some of the so-called softwoods are harder than balsa. It has a wide variety of uses, though many people seem to underestimate its value.

There are about 20 grades of balsa falling into two categories. One category is appearance; balsa is graded for cosmetics and color. The model airplane business wants top grade white balsa with no defects.

The other prime grade category has to do with mechanical properties of weight and density. As a rule of thumb, the lighter the balsa, the lower the mechanical properties.

Balsa is a high-tech core material. Its many uses include boat hulls, aircraft flooring, chemical containment tanks, and bathtub and shower bottoms. Other uses include artificial limbs and caskets, cargo containers with balsa cores, as well as a car, the Chevrolet Express, which incorporates balsa in its design.

It is well known by the name of balsa in the United States, but goes by a variety of names in other countries, among them: lanero, Cuba; topa, Peru; tami, Bolivia; polak, Nicaragua. Balsa trees grow to an average height of 70 feet, but the quality of the wood depends a lot on the age of the tree when harvested. The older trees run the risk of rotting at the base. Young trees are lighter as well, averaging 8.5 pounds per cubic foot, while the older, very absorbent trees can weigh as much as 25 pounds per cubic foot to 25 pounds per cubic foot, the average commercial weight falls between 6 and 16 pounds per cubic foot, with a specific gravity of 0.16

Balsa is a light colored wood, but it has a range of light colors from almost white to oatmeal, to a pink-tinged yellow. It has a silky texture.

For commercial purposes, the white to off-white sapwood is used. In larger trees, the heartwood deepens to a pale brown. Balsa has a fine texture and a straight, open grain.

Seasoning is a tricky procedure with balsa, which in its green state has 200 to 400 percent moisture, with the ability to absorb up to 792 percent. Because of the risk of fungal discoloration and decay, experts recommend a quick conversion and drying process right after the trees are cut. However, balsa can still exhibit heavy degrade.

Balsa is considered an easy-to-work-with wood, provided that sharp hand or power tools are used. It has a very slight blunting effect. While it will take nails and screws easily, they rarely hold because of the wood's softness, so glue is used more effectively. Balsa can be stained and finished, but will absorb much of what is applied