The mathematical model in Sawing Decision Maker is based on a tapered cylinder. The cylinder, or log, is easily changed with respect to taper, top diameter and length. The yield is based on the nominal dimension of the boards and length with or without wane. The yield is also expressed as log volume needed for production of one cubic meter of boards. The log volume is calculated in three ways, true volume (with or without bark) or top cylinder volume. The true volume is the volume of the tapered cylinder. The top cylinder volume is based on top diameter and length. The calculation will give theoretical values. In practice the roundness of a log is not a perfect circle, the logs are not perfectly straight and will have sweep and crook. The measurement accuracy of logs and boards can also affect the results. Other factors include errors in feeding etc.
Sawing Decision Maker (SDM) is available in four different languages, English, German, Finnish and Swedish. As of today, the program is used by more than 50 sawmills in Sweden, Finland, Norway, Estonia, Lithuania and Poland. The program is used by both large sawmills with extensive presorting of logs and sawmills with little or no sorting and individual optimization for each log. Questions like “how should we process this new order of board dimensions?” can easily be analyzed. SDM is a quick and analytical tool for the complete process. The program can be customized to work for both small and large sawmills.