Lumber grading

Lumber grading is a way of evaluating the surface quality of a board according to certain standards, taking into account factors such as the number, size and degree of defects in the wood. The goal is to insure that woodworkers get what they pay for; a board of a certain grade of wood bought in Maine will closely resemble a similar-grade board purchased in New Mexico.

At first glance, the rules of grading may seem arbitrary. For starters, the standards are different for softwoods and hardwoods, the result of the end use of each type of wood. Softwoods are primarily used in construction, so a grader may assume that a softwood board will be used as is, with no further surfacing. Hardwood boards, on the other hand, are almost always planed, crosscut and ripped into smaller pieces to fit a particular piece of furniture. Added to that is the fact that, while there is one standard for hardwoods, softwoods are further divided into separate groups and graded according to rules established by different organizations. Taking the time to become familiar with hardwood and softwood grading will pay dividends.

A sound understanding of the grading system enables you to select the most appropriate board for the job at hand; it can also save you money. There is no need, for example, to order long planks of top-grade FAS (or Firsts and Seconds) lumber if most of the pieces of the cabinet you intend to build are only three or four feet long. No. I Common, which is considerably cheaper, and will be adequate once you have cut out the defects. Lumber producers and vendors have long found it advantageous to study wood types and set rules for grading to guarantee a uniform product.

One of the earliest instances of grading occurred in 1764, when Sven Aversdon of Stockhohn divided Swedish pine into four categories – best, good, common and culls. During the l8th century, appearance was the primary criterion [kraɪ'tɪərɪən] for grading wood, but as knowledge of wood proper ties increased, standards changed to include strength and the amount of clearer usable wood in each board. The best way to become familiar with grades is to visit a lumberyard and examine stock firsthand. Get to know how a hardwood grade like FAS differs from No. I Common. And when you select lumber, try to picture how each part can be cut out of a board with the least waste.

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