Bead: from jewelry to joinery

To the general public, a bead is a small decorative sphere with a hole drilled through it, strung on thread or wire to make jewelry or ornament. The word likely comes from Old English bede, meaning prayer, because beads were used to count prayers on a rosary. The visual association with small round objects is ancient and universal.

In woodworking, a bead is something entirely different: a convex, rounded profile cut into the edge or surface of wood. It is typically a half-circle or quarter-circle in cross-section, and it is almost always outlined by a sharp, narrow groove called a quirk that separates the bead from the adjacent flat surface. This molding serves both decorative and practical purposes, softening hard edges and catching light along the grain.

The connection between the two meanings lies in the shape. A bead molding, when viewed in profile, echoes the curve of a sphere. Woodworkers named this profile after the jewelry because both share that smooth, rounded geometry. Over time, "bead" became the standard term for this particular molding cut, and it remains so in furniture making, cabinetry, and architectural millwork.

The bead appears in other trades as well. In tire service, a bead breaker is a tool that separates the bead of a tire (the edge that seats on the rim) from the rim itself. Here the word refers to the stiffened edge of the tire casing, which is shaped somewhat like a rounded bead where it grips the wheel. The industrial usage parallels the woodworking one: both describe a rounded, structural element that was named for its resemblance to the spherical object.

Beads in wood are cut with specialized router bits or molding planes, and they appear on everything from picture frames to door casings to decorative panels. The quirk that defines a bead is essential to its visual and functional character, creating shadow lines that emphasize the molding's profile and protect it from damage where it meets the flat surface.