The Effect of Log Rotation On Value Recovery In Chip And Saw Sawmills

Advances in three-dimensional scanning techniques and computer optimization permit real time solution and implementation of optimal log rotation before it is fed into the chipper heads. A random sample of 834 S-P-F logs from the interior of British Columbia were examined using simulation to determine the effects of log rotation strategies on value recovery for a small log Chip and Saw. Both log sweep and cross-sectional eccentricity are shown to cause significant reductions in value recovery. Eight rotation placements from 0° to 315° were studied to determine if a single rotational placement could be found that performs best. On average, the "horns up" position (0° rotation) was found to significantly outperform all others in maximizing value recovery. The ability to rotate each log into the optimal position produced significant benefits. The benefits were more highly related to the degree of cross-sectional eccentricity present in the log rather than the degree of sweep present in the log.