THE EFFECT OF LOG GIRTH ON PRODUCTION AND RECOVERY IN A JARRAH SAWMILL

Studies in a Western Australian jarrah sawmill showed that log breaking down rate was increased by 86 per cent., and sawn production rate by 24 per cent., by an increase of 3 ft. 6 in. in log girth (from approx. 4ft. 9 in. to 8 ft 3 in.) At the same time, sawn recovery was raised by approx. 4 per cent, of the Hoppus log volume. Based on all personnel under the mill roof, a sawn output of 45½ sup ft. per man-hour was obtained. Recovery averaged 42 per cent. (Hoppus basis).