Methods of Cutting Logs Into Lumber and Veneers
Plain-sawed, Quarter-sawed Lumber, and Veneers | |
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(a) Plain-sawed - When the log is sawed lengthwise and tangent to the annual growth rings or at right angles to the medullary rays the cut is called "plain-sawed" lumber in hardwoods and "flat-grain" or "slash-grain" lumber in softwoods. This is the most economical manner of producing lumber with the least waste. Also in many trees such as ash, chestnut, elm, and most softwoods ( conifers) the plain-sawed method shows the best grain and figure in the wood. (b) Quarter-sawed - When the log is sawed parallel to the radius or rays, across the rings from the bark to the center, the cut is called "quarter-sawed" in hardwoods and "edge-grain," "vertical-grain" or "rift-sawed" lumber in softwoods. Some species have very prominent medullary rays which accounts for the beautiful figure shown in such quarter-sawed woods as oak, maple, and sycamore.
( c) Veneers - Veneers are produced in four ways, namely:
Sawed or sliced veneers may be cut from a veneer log in any direction. Sawed veneer may be cut so as to obtain a "sliver grain" or "quartered sawed" figure. In rotary veneer the growth-ring figure of the log is continuous and extends through the log so that as a thin slice is taken off, the pattern is the same, and one piece can be switched with another cut from the same veneer bolt. Usually the entire volume from a veneer bolt is sold commercially as a unit because no two logs have the same figure. Veneers usually range in thickness from 1/28 to 3/16 inch thick. Some veneers, however, are cut paper thin. | |
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