Sorting Logs and Lumber for Stiffness Using Director HM200


  • Peter Carter
  • Shakti Chauhan
  • John Walker


Director HM200, acoustic velocity, density, stiffness, radiata pine


Acoustic tools such as the Director HM200 are able to sort logs and boards according to their intrinsic stiffness. Here, some uses of such tools are demonstrated. First, six logs are analyzed before sawing into cants and individual boards. Second, the same approach is reconsidered from basic principles, emphasizing the variety of investigative projects to match the species-specific responses to acoustics and the need to match local resources to local markets. In both instances, correlations between acoustic properties measured in logs are related to those from cants and boards. The offsetting effects of changes in stiffness and density in determining acoustic velocity are discussed. The intention is to emphasize future possibilities for commercial application.


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