Quarter sawing

Quarter sawing or quartersawing is a woodworking process that produces quarter-sawn or quarter-cut boards in the rip cutting of logs into lumber. The resulting lumber can also be called radially-sawn or simply quartered. There is widespread confusion between the terms rift sawn and quarter sawn, with the terms defined both with opposite meanings and as synonyms.

Quarter-sawn boards have greater stability of form and size with less cupping (compared to flatsawn boards), shrinkage across the width, shake and splitting, and other good qualities. In some woods such as oak, the wood grain produces a decorative effect which shows a prominent ray fleck, while sapele is likely to produce a ribbon figure.

Quarter sawing is a process for rip cutting logs into lumber. It produces quarter-sawn or quarter-cut boards. The resulting lumber can also be called radially-sawn or simply quartered.

Wood cut in this way is prized for certain applications, but it will tend to be more expensive as well. In cutting a log, quarter-sawn boards can be produced in several ways. However, if a log is cut for maximum yield, it will produce only a few quarter-sawn boards among the total. Conversely, if a log is cut to produce only quarter-sawn boards, there will be considerable waste.

When boards are cut from a log, they are usually rip cut along the length (axis) of the log. This can be done in three ways: plain-sawing (most common, also known as flat-sawn, bastard-sawn, through and through, and tangent-sawn), quarter-sawing (less common), or rift sawing (rare).

In flat sawing, the log is passed through the blade, cutting off plank after plank without changing the orientation of the blade or log. The resulting planks have different growth ring orientations when viewed from the end. The relative angle that forms the rings and the surface goes from almost zero degrees in the external planks to nearly ninety degrees at the core of the log.

Quarter sawing gets its name from the fact that the log is first quartered lengthwise, resulting in wedges with a right angle ending at approximately the center of the original log. Each quarter is then cut separately by tipping it up on its point and sawing boards successively along the axis. The result is boards with growth rings mostly perpendicular to the faces. Quarter sawing yields boards with straight striped grain lines, greater stability than flatsawn wood, and a distinctive ray and fleck figure. It also yields narrower boards, because the log is first quartered, which is more wasteful.

Quarter-sawn boards can also be produced by cutting a board from one flat face of the quarter, flipping the wedge onto the other flat face to cut the next board, and so on.