Two-Dimensional Geometric Theory for Maximizing Lumber Yield From Logs


  • Yage Zheng
  • Francis G. Wagner
  • Philip H. Steele
  • Zhendong Ji


Log breakdown, log sawing algorithm, cant sawing


A two-dimensional geometric theory for maximizing lumber yield from logs was developed. Centered cant sawing solutions for both circular and elliptical shaped logs were derived. Sawline placement for maximum yield is dependent upon the diameter of round logs or upon the cross-sectional axis of elliptical logs. The width of the face of the cant is equal to 0.707 times the diameter or parallel-axis of the log. Slab thickness is equal to 0.147 times the diameter or perpendicular-axis of the log. It assumes circular and elliptical log shapes and provides a method that may substantially reduce computation time when applied to computerized log breakdown decisions.


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Research Contributions