Glossary of Wood Words
Don't know a burl from a bow, a jig from a collet? Here s a glossary of some woodworking terms guaranteed to help you sound like a pro.
A - E
Adhesive: A substance that bonds two other materials together. Commonly referred to as glue.
Air-dried lumber: Boards that have dried naturally by stacking them in the open air, as shown above and right. Air flows between the boards, allowing the moisture in the wood to evaporate. Air drying can take as long as one year per inch of board thickness. In all but the driest regions, moisture content rarely falls below 12 to 20 percent without additional drying indoors.
All-thread: Steel rod (sometimes called drill rod) that has been threaded along its entire length. (Picture a long bolt without its head.) The material comes in a variety of diameters and threads per inch (tpi), and usually measures 36" long. You hacksaw it to any desired length to create everything from custom bolts to adjustment mechanisms for jigs.
Antikickback pawls: Attached to a tablesaw's blade-guard system, these spring-loaded metal plates with sawtooth edges work in conjunction with the splitter. In the event of workpiece kickback, the pawls dig into the wood to prevent it from being propelled toward the operator, shown right.
Apron: A horizontal piece that supports the top or seat and connects the legs of a table or chair.
Arbor: In a tablesaw, the threaded shaft on which the saw blade mounts and is held in place with a nut, shown right. Riding on bearings, the arbor gets rotated by the drive belts to spin the blade. Most saws with 10" blades have a 5/8"-diameter arbor.
Auxiliary fence: A temporary (sometimes sacrificial) fence attached to a tablesaw rip fence or miter gauge, or to some other machine table, or protect a cutter or bit while providing full workpiece support, shown right.
Backer board: A sacrificial board placed behind a workpiece during a cutting or shaping process. The backer board supports the wood to prevent chip-out as the blade or cutter exits the workpiece, shown right.
Bird's eye: Small, circular areas on wood surfaces caused by indented wood fibers.
Biscuit: A common name for football-shape wooden "plates" used in joinery. Made from compressed beech, biscuits fit into slots cut with a biscuit joiner (see right), or a slot-cutting bit in a router. Biscuits increase glue surface in the joint for improved holding power and hold the joint in alignment during clamping. Three traditional sizes (#0, #10, #20) are most common, but several other sizes exist.
Biscuit joiner: A specialized power tool made to cut slots that accept hardwood biscuits. The tool most often resembles an angle grinder with a precision fence and base added on. These parts of the tool work together to align a retractable circular blade that plunges into the mating joint members at the desired slot location. Each plunge creates one half of the biscuit slot.
Blade runout: Runout in circular-saw blades is measured by the amount of side-to-side movement in the blade body.
Blade guard: On a tablesaw, a plastic or metal shroud that covers the blade to prevent the saw operator from placing his hands in contact with a spinning blade. The device also prevents small cutoffs from being thrown toward the front of the tablesaw and the operator.
Board foot: The standard unit of measure for hardwood lumber. Because hardwoods often sell in random widths and lengths, a board foot measures thickness, width, and length to determine the total volume of wood in the board. One board foot is a piece 1x12x12". Use the following formula to calculate the board foot measurement of any piece of lumber.
Bow: A warp in which the ends of a board or wooden member curve in the same direction away from the desired plane, usually along the length.
Burl: A swirling, twisted figure in wood grain caused by growths on the outside of the tree or root.
Burnisher: A round or triangular steel rod with a handle that is used to produce the hooked cutting edge on a cabinet scraper.
Cabinet carcase: The box-like component that is fitted with drawers, shelves, and/or doors in cabinet construction.
Centerline: A layout line drawn at the center of the thickness, width, or length of a workpiece and sometimes marked with the CL symbol. Typically, the centerline marking is used without an accompanying dimensional measurement.
Chamfer: The edge of a board that has been beveled at an angle.
Checks: Splits running along the grain in wood that occur most frequently in end grain.
Chip-out: Splinters of wood that break away from a workpiece during a cutting or shaping process, shown right. Combat chip-out by using sharp blades and bits, backer boards, and slower feed rates.
Clamp blocks: Wedge-shaped blocks temporarily spot-glued to workpieces so that the parts can be clamped together for gluing.
Climb cut: A routing operation during which the router moves in the same direction as the bit's rotation, rather than against the rotation, as is normal. The result is a cleaner, but harder-to-control, cut. Always make light cuts when climb-cutting.
Collet: A metal slotted sleeve that holds a router bit in place in the router shaft. Secured by a nut, the collet clamps around the shank of the bit. Many routers come with both 1/4" and 1/2" collets to accommodate available bits, but some inexpensive models are equipped with only a 1/4" collet. Some include a 1/2" collet and a reducer sleeve, as shown, below. Collet styles vary: they typically are not interchangeable between router brands.
Collet runout: The amount of deviation from center (wobble) in a router collet, measured in thousandths of an inch.
Contact adhesive: A thin, rubber-based adhesive, used most often for bonding plastic laminate to substrates. You apply the adhesive to both mating surfaces, then allow it to dry until tacky. When joined, the surfaces bond on contact.
Core: In sheet goods, the layer or layers of material between the face and back veneers.
Counterbore: A stopped hole in a workpiece that allows you to set a screwhead below the surface of the wood. You can plug the counterbore to hide the head, shown right.
Countersink: A shallow, conical hole in a workpiece that matches the shape of a flathead screwhead. When used without a counterbore, it positions the head flush with the surrounding surface, shown above.
Crosscut: A cut across the wood grain.
Cutting Diagram: An illustrated guide that depicts the quantities and sizes of boards required for a project as well as where each part should be laid out to minimize waste. While extremely handy for defining lumber needs, cutting diagrams can't account for grain variations in solid wood stock or sheet goods, or for defects in solid stock. So, use a cutting diagram as a guideline only.
Dado: A square-cornered channel cut across the wood grain, typically using a dado set or a straight router bit, shown right.
Dead-blow hammer: A plastic-bodied hammer with a hollow head that's partially filled with steel shot. When struck against an object, the shot shifts quickly to that end of the head. This transfer of mass prevents the head from bouncing and delivers a solid blow without marring workpieces. Dead-blow hammers are ideal for assembling and disassembling projects.
Dry-fit: Temporarily assembling a project without glue or permanent fasteners. Use this technique to check the accuracy and fit of joinery, and to determine the sequence for final assembly.
Dry time: The amount of time it takes for glue in an assembled joint to completely dry or cure and achieve full strength. This time varies from a few hours to 24 hours, depending on the glue type. Also called cure time.
Ease: To slightly relieve, or "soften," a sharp edge on a piece of wood. This is generally accomplished by sanding, planing, or rounding the edge with a 1/8" round-over router bit.
Edge grain: Wood characterized by the growth rings being 45 or more degrees, preferably perpendicular, to the surface of a board.