Balsa (Ochroma pyramidale, synonym O. lagopus) is a large, fast-growing tree that can grow up to 30m (100ft) tall, native to tropical South America north to southern Mexico. It is evergreen, or dry-season deciduous if the dry season is long, with large (30–50 cm, 12-20 in) weakly palmately lobed leaves. The name balsa derives from Spanish for a raft. Despite being very soft, balsa is classified as a hardwood, and is the softest commercial hardwood.
The timber is very soft and light with a coarse open grain. The density of dry balsa wood ranges from 100–200 kg/m³ (6.24-12.49 lb/ft³), with a typical density of about 140 kg/m³ (8.74 lb/ft³) (about one third the density of other hard woods). It is also a very popular material to use when making wooden crankbaits for fishing, as it is low density but high in strength. Balsa wood is used to make very light, stiff structures in model bridge tests and for the construction of light wooden aeroplanes, most famously the World War II de Havilland Mosquito. It is also used in the floorpan of the Chevrolet Corvette Z06 sandwiched between two sheets of carbon fibre. In table tennis bats, a balsa layer is typically sandwiched between two pieces of thin plywood. Balsa wood is also used in laminates with glass-reinforced plastic (fiberglass) for making high-quality balsa surfboards and the decks and topsides of many types of boats, especially pleasure craft under 30m (100 ft) in length.
Balsa wood is often used as a core material in composites, and as a result many wind turbines are made partially of balsa. It also remains a popular material for model aircraft, offering an excellent balance of strength and lightness.
The timber is very soft and light with a coarse open grain. The density of dry balsa wood ranges from 100–200 kg/m³ (6.24-12.49 lb/ft³), with a typical density of about 140 kg/m³ (8.74 lb/ft³) (about one third the density of other hard woods). It is also a very popular material to use when making wooden crankbaits for fishing, as it is low density but high in strength. Balsa wood is used to make very light, stiff structures in model bridge tests and for the construction of light wooden aeroplanes, most famously the World War II de Havilland Mosquito. It is also used in the floorpan of the Chevrolet Corvette Z06 sandwiched between two sheets of carbon fibre. In table tennis bats, a balsa layer is typically sandwiched between two pieces of thin plywood. Balsa wood is also used in laminates with glass-reinforced plastic (fiberglass) for making high-quality balsa surfboards and the decks and topsides of many types of boats, especially pleasure craft under 30m (100 ft) in length.
Balsa wood is often used as a core material in composites, and as a result many wind turbines are made partially of balsa. It also remains a popular material for model aircraft, offering an excellent balance of strength and lightness.
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