centerpin

Centerpin, written centerpin or center pin in some contexts, is a term used across several technical fields to denote a central pin or axis around which components are aligned, rotated, or connected. The exact meaning varies by domain, spanning from a specialized fishing reel to mechanical locating pins and central contacts in electrical connectors.

In fishing, centerpin refers to both a mode of float fishing and the reel used for it. A centerpin reel mounts a fixed spool on a central axis, usually with little or no drag, so line is released primarily under the angler’s control rather than through a drag mechanism. The technique emphasizes a long, precise drift with the current, typically on rivers using float rigs and long rods. Centerpin fishing is valued for sensitivity and line control, but has a learning curve and can involve specialized gear that is relatively costly.

In mechanical engineering, a center pin is a locating or pivot pin placed at or near the center of a rotating component, such as a wheel, gear, or linkage. It serves to align parts, support rotational movement, or act as a hinge point. Center pins may be used in conjunction with bearings, bushings, or collars and come in various tolerances and fits depending on the application. Related terms include dowel pins and hinge pins, which perform similar centering and alignment functions in assemblies.

In electrical and connector contexts, the center pin describes the central conductive contact in many coaxial or barrel-style connectors, where the pin carries the signal or power and the surrounding shell provides ground or shielding. The specific geometry and terminology vary by standard.

Notes: spelling varies; centerpin (one word) is common in fishing communities, while center pin may be used in other technical fields.