halfround

Halfround, often written as half-round, is a term used across crafts to describe a semicircular cross-section or profile. It denotes a shape that is half of a circle, producing a curved exterior surface and, in many cases, a flat face on one side. The concept appears in geometry, tooling, trim work, and architectural elements where a smooth, rounded edge or channel is desired.

In tools and metalworking, a half-round file is a common hand tool with a semicircular cross-section. One side is flat and the other is curved, allowing the user to remove material from concave curves and rounded transitions or to work both flat and curved surfaces. Half-round files come in various coarseness and are used in metalworking, woodworking, and pattern work for shaping rounded contours and blending joints.

In carpentry and architecture, half-round appears as both a molding profile and a structural or decorative feature. Half-round molding provides a semicircular edge or surface along walls, doors, windows, or cabinetry, offering a gentle curvature that softens joints and adds visual interest. Half-round profiles are also used in architectural gutters and downspouts, where a semicircular cross-section channels rainwater and evokes classical or traditional aesthetics.

Other uses include profiles in stock shapes, trims, and channels where a semicircular cross-section is desired for functional or decorative purposes. The term is also encountered in various regional woodworking and metalworking catalogs to describe similar semicircular forms.

See also: molding profiles, fillet, guttering, file types.