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ou can buy the lumber for your woodworking project from several sources, each with its own advantages and drawbacks. The local lumberyard is often the most convenient supplier, but the selection may be limited to construction woods such as pine, spruce, and other softwoods. Though you may find the occasional cache of hardwood at a lumberyard, you will probably have to venture farther afield, consulting woodworking magazines to find dealers who specialize in the hardwoods used in cabinetry. Prices for good hardwood lumber can be high, but as is often the case, you will generally get what you pay for.
Sometimes you can buy locally cut lumber from a small sawmill, but the
wood will often need to be seasoned and surfaced. Recycled boards are growing in popularity, a result of the scarcity of certain woods and the growing sense of environmental responsibility felt by many woodworkers. Whether removed from an old barn or a piece of timeworn furniture, such wood may be relatively inexpensive and, because it often originates from old growth timber, it can be visually and structurally superior to the small billets of younger lumber available today.
Before ordering your wood, consider your requirements carefully and refer to the following tips to help you get what you need at a reasonable cost.
•Species: Ask for the specific wood species, not a broad family name. For
example, order Western red cedar, not simply cedar. To be absolutely sure, learn the botanical name of the wood you want and ask for it.
• Quantity: Let your supplier know whether you are ordering in board feet or lineal feet. A lineal foot refers to a board’s length, regardless of its width and thickness. The board foot is a measure of the volume of wood; it is usually necessary to refer to board feet for ordering hardwoods, which are often available in random sizes only.
•Size: Wood is sold in nominal rather than actual sizes, so make allowances for the difference when ordering surfaced lumber. A nominal 2-by-4 is actually l! T’-by-3/f". The thickness of wood is often expressed as a fraction in quarters
Ordering lumber by the board foot
The board foot is a unit of measurement commonly used when dealing with hardwood lumber. As shown below, the standard board foot is equivalent to a piece of wood 1 inch thick, 12 inches wide, and 12 inches long. To calculate the number of board feet in a particular piece of wood, multiply its three dimensions, then divide the result by 144 if the dimensions are all in inches, or by 12 if one of the dimensions is in feet.
The formula for a standard board:
1" x 12" x 12" + 144 = 1 (or 1" x 12" x Г + 12 = 1)
So if you had a 6-foot-long l-by-4, you would calculate the board feet as follows: 1" x 4" x 6′ + 12 = 2 (or 2 board feet). Other examples are shown in the illustration. Remember that board feet are calculated on the basis of nominal rather than actual dimensions.
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of an inch. A 2-inch-thick board, for example, is expressed as %; surfacing will reduce it to 1V* inches. With unsurfaced or green wood, the nominal and actual dimensions are the same.
•Grade: The primary difference between high and low grades of hardwood lumber is appearance rather than strength. Because the grade of a board is determined by the proportions of clear wood it contains, large high-grade boards are far more expensive than lower-grade boards. If you need only smaller high-grade pieces you can cut them out of a lower-grade board, at great savings. Consult your local dealer for a chart of the different grades available.
•Seasoning: Lumber is sold either kiln-dried (KD) or air-dried (AD). The
primary difference between the two is the moisture content (MC) of the wood. Kiln-dried wood has a moisture content of about 8 percent; it will not dry any further when used for indoor furniture. Air-dried wood has an MC of 12 to 15 percent. This wood is often chosen by carvers, or by woodworkers who prefer to dry their own wood.
• Surfacing: Surfacing refers to how wood is prepared at the mill before it comes to the lumberyard. Hardwood lumber is usually surfaced on both faces (S2S). If you have a planer and a jointer, buying rough lumber and surfacing it yourself will prove less expensive.
Making and using a cutting list
A cutting list records the finished sizes of lumber needed for a particular piece of furniture. If one is not included with the plans you purchase, you will have to make your own based on a sketch of the design. Use the formula shown on page 16 to total the number of board feet for each component of the project; add 20 to 40 percent (depending on the species) to account for waste and defects in the wood. For the bookcase shown at right, which totals roughly 14 board feet, you should purchase 17 to 20 board feet of % lumber in addition to the plywood for the back of the case. As shown below, a cutting list should include the name of the component, the quantity, the dimensions of each piece, and the wood species selected for the project. For convenience, assign each piece a key letter for later reference.
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CUTTING LIST
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