Whether you see woodworking as an art or a craft, your finished piece begins with a great piece of wood. As a woodworker, buying wood can be a challenging experience. You have to think about a lot of details such as the grade and cut of the wood and the way it's sized. The following sections help you make sense of these details.
Take a pencil, measuring tape, scrap paper, small block plane (to check out the color and grain) and a calculator to the lumberyard and write down all the dimensions and total board feet for each board. This way you can double-check the salesperson's calculations and make sure you aren't overcharged.
Wood grades
Wood grades refer to the number and severity of the defects in a board. The following list explains the different wood grades, according to the National Hardwood Lumber Association (or NHLA for short).
Firsts: Very few, if any, noticeable defects.
Seconds: The occasional knot or other surface defect. Firsts and seconds are often grouped together and referred to as FAS (firsts and seconds). These are the grades you want for furniture building.
Selects: A few more defects, but nothing so big or frequent that it can't be cut out. Avoid this grade for fine furniture, though, because it adds more work to the process.
Four grades of Common (#1, #2, #3a, #3b): Too many defects to use for furniture.
Types of wood cuts
How wood is cut affects its quality. The following list explains the types of cuts:
Plain-sawn: The most common boards at your lumberyard. They have growth rings that run less than 30 degrees against the face of the board. The face grain looks somewhat circular and wavy.
Rift-sawn: These boards have growths rings that meet the face between 30 and 60 degrees. Rift-sawn boards have a straight grain pattern as opposed to the circular pattern of the plain-sawn boards. They're also more stable and more expensive than plain-sawn wood.
Quarter-sawn: These boards have growth rings not less than 60 degrees from their face and a straight grain pattern with a flake or ribbon-like figure in the wood. Quarter-sawn boards are more stable and expensive than the other types of boards and you can only find them in a few species of wood, such as white oak.
Wood defects
It's okay to buy wood with knots, splits, cracks, and checks. These defects affect only a small area of the board (if they exist over the majority of the board, don't buy it), so you can plan your cuts around them. Avoid boards with warps, twists, or bows. It takes a lot of time to flatten a board that has one of these defects. To test for these defects, place one end of the board on the floor and hold the other end to your eye. The board should be straight and true. If not, leave it there.
Sizing up the wood
Wood is sold two ways: dimensional and by the board foot:
Dimensional wood is smooth on all four sides, cut to precise widths and thicknesses, and is sold by the linear foot or the board.
Wood sold by the board foot may or may not be smooth on all sides and only one edge may be square. A board foot is a board that is 1 inch thick (called 4/4) by 12 inches wide by 1 foot long. To figure out how many board feet are in a piece of wood, multiply its length (measured in feet), width, and thickness (measured in inches) and divide this number by 12.