roundhole

Roundhole is a term used to describe a circular opening in a solid object. In engineering and fabrication, a roundhole is created to accept a fastener, dowel, pipe, or to provide ventilation. The defining feature is a circular cross-section, specified by a diameter, with tolerances and roundness affecting fit and performance.

Common methods to produce roundholes include drilling, punching, boring, and reaming. Deburring and edge finishing, such as chamfering, are often employed to prevent damage, reduce stress risers, and improve assembly.

Variants include through holes, which pass completely through the part, and blind holes, which terminate before the far surface. In assembly, roundholes are paired with matching shafts or pins; clearance holes allow easy insertion, while interference or press-fit holes yield a tighter connection.

Applications span furniture and cabinetry, metal fabrication, plumbing, and electronics. Through-holes in printed circuit boards, for example, accommodate component leads. In mechanical design, roundholes are described by diameter and depth, with tolerances and fits (clearance, transition, or interference) influencing function.

Design considerations include edge treatment (chamfer or countersink for screw heads), material thickness, potential for stress concentration, and surface treatments such as plating or coating. The term “roundhole” is generally descriptive and may be specified differently across fields, standards, or engineering drawings. See also bore, drill, ream, punch, clearance hole, blind hole.