|Kris||05/13/10 07:56 PM|
Woodgrain in a log is comprised of a series of concentric rings beginning in the center. Plainsawn boards have substantially different grain patterns depending on where they were cut out of the log. Since wood expands and contracts in different ways with respect to grain, plainsawn lumber is typically less stable than the alternatives listed below. The tendency of wood to expand and contract is called wood movement. Plainsawn wood often has interesting grain patterns, often called cathedrals, that are not created by other types of cutting.
Riftsawn lumber is much more stable than plainsawn lumber. As shown in the drawing, each board has the same relation to the log, and therefore each board will have the same grain pattern. Furniture made out of riftsawn wood has more of a uniform appearance due to the similarity of grain patterns among different boards. Unfortunately, rift-sawing provides very poor yield, and as is evident in the drawing, lots of wedge-shaped scraps are produced. The low yield has ensured that riftsawn wood is a rarity at the lumber yard.
Quartersawn boards are created by first cutting a log into quarters and then creating a series of parallel cuts perpendicular to the tree's rings. The yield is not as substantial as in plainsawing but much greater than in riftsawing. The grain in quartersawn wood is relatively consistent, and therefore the end product is stable and often preferred by woodworkers and furniture-makers. Quartersawn wood may include medullary rays and wavy grain patterns that some people prefer to the figures that are revealed with alternative sawing methods.
Since the yield produced by quartersawing wood is substantially lower than other plainsawing, the cost is relatively high. Oak is the most common quartersawn wood; on occassion one may be also able to find quartersawn walnut, cherry, and maple. The increased stability makes quartersawn wood highly sought after for string instrument necks and fret boards. The neck of a guitar, bass or violin, for example, should remain stable throughout their lives; quartersawn wood helps ensure that instrument's sound remains as invariable as possible.