Pernambuco wood (Caesalpinia echinata) used in the manufacture of bows for string instruments

The anatomy and the physical, mechanical, acoustical and chemical properties of pernambuco wood (Caesalpinia echinata Lam.) were investigated to determine factors that could explain the different quality of sticks used in bow manufacture. Eighteen sticks were classified into four classes (A to D with A being the best) according to their potential quality for bow manufacture. Selection of samples was based on the experience of a bow maker and on some nondestructive tests. The A-class sticks had a lower frequency of vessels and rays and a higher percentage of fibers when compared to the other classes. They also had higher values of density, speed of sound propagation, modulus of elasticity and modulus of rupture. Klason lignin content was higher in the A-class sticks but the quantity of hydrosoluble and ethanol/benzene soluble extractives was lower. The values of density and speed of sound propagation obtained by nondestructive and destructive methods were similar showing the applicability of the former in the prior selection process of the sticks.