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Methods of Sawing | |
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| Plain Sawing
(Flatsawn) Plain sawing is the most common method of sawing and consequently most lumber is plain sawn, unless specified otherwise. Plain sawn lumber is obtained by making the first saw cut on a tangent to the circumference of the log and the remaining cuts parallel to the first. This method provides the widest boards and least waste; therefore, it is the most economical. About half of the lumber produced by plain sawing is of tangential grain and the other half is of radial grain.  Tangential
grain is usually called flat grain and is easily recognized
by its cathedral (Gothic arch) effect. Lumber is considered
flat grained when the annual growth rings make an angle of less
than 45 degrees with the surface of the board.Radial grain is known as vertical grain or edge grain, and is generally more dimensionally stable than flat grain. Lumber is considered vertical grain when the annual growth rings make an angle of 45 to 90 degrees with the wide surface of the board. Quarter Sawn Quarter sawn lumber is produced by first quartering the log and then sawing it perpendicular to the growth rings. All of the boards sawn thus are of radial grain. This method of sawing produces relatively narrow boards and creates more waste. For these reasons (and the additional handling involved) quarter sawn lumber is much more expensive than plain sawn. Rift Sawing Rift sawing is very similar to quarter sawing, and has the same advantages and limitations. This method of sawing accentuates the vertical grain and minimizes the flake, common in quarter sawn oak. The angle of the cut is changed slightly so that fewer saw cuts are parallel to the medullary rays, which are responsible for the flake effect. Availability Red oak, white oak and the mahoganies are available in quarter sawn lumber. Red oak and white oak are also marketed as rift grain. Some of the softwoods, principally redwood and fir, can be obtained as vertical grain. |
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