Abstract
Wood remains the material of choice for stringed musical instruments. However, as supplies of suitable wood decrease, a need to maximize the use of available timber arises. Since large variations exist within a species, manufacturing processes require direct measurements of the mechanical properties of a given specimen in order to construct acoustically consistent instruments. This paper reports on the application of non-destructive mechanical property tests developed to be used on a single wooden specimen. In this way, relationships between mechanical properties of clear, straight-grained, quartersawn timber can be investigated and the number of measurements during manufacturing can be reduced. Measured properties include density, moisture content, radial and longitudinal Young’s moduli, shear modulus and Poisson’s ratios in the longitudinal–radial plane. Furthermore, natural frequencies of theses specimens have been measured for the rectangular plates having simply supported boundary conditions. Sitka spruce (Picea sitchensis) has been studied. Relationships between various mechanical properties are found, and suggestions for using Poisson’s ratios are proposed. These relationships are shown to reduce the number of measurements required to construct acoustically consistent instruments in musical instrument manufacturing. In particular, it is shown that measurements of the Young’s moduli in both the radial and longitudinal directions would be suitable for describing the important mechanical properties of such soundboard wood. The natural frequencies of the tested plates were also calculated from the measured properties and compared to values obtained experimentally. Great correlation is found between the theoretical model and experimental results for the simply supported rectangular plates.
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The authors would like to acknowledge the generous support provided by the Natural Science and Engineering Research Council of Canada.
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Dumond, P., Baddour, N. Experimental investigation of the mechanical properties and natural frequencies of simply supported Sitka spruce plates. Wood Sci Technol 49, 1137–1155 (2015). https://doi.org/10.1007/s00226-015-0759-z
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DOI: https://doi.org/10.1007/s00226-015-0759-z