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Abstract
This paper discusses four classes of lumber timming machines applicable to the planning mill. The classification is made according to function as follows: Irregularity or defect removal to increase the value of residual portion. Double end trimming to a length standard acceptable by the trade, trimming to specified length of the higher grades of stock after it has been tied into bundles, and end matching to random length stock to permit fuller utilization of the shorter lengths.
Citation
Koch, Peter. 1952. Some technical aspects of trimming lumber in the planing mill. In: The American Society of Mechanical Engineers: 1-32