This Scale was developed in 1906 and is based on a reasonably accurate mathematical formula. The rule allows for a 1/4-inch saw kerf (circular mills) and a fixed taper allowance of 1/2 inch per 4 feet of log length. Deductions are also allowed for shrinkage of boards and a waste thickness that varies with the log diameter. Overall, the International 1/4-Inch Log Scale is the most consistent and is often used as a basis of comparison for log rules.
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