trimvlak

Trimvlak is a Dutch term used in technical disciplines to denote a plane that is used to trim or clip a surface or solid. It denotes a flat, infinite plane in geometric space that intersects a model to remove material beyond the plane, leaving only the portion on or inside the designated side.

In CAD and 3D modeling, a trimvlak defines the boundary of a trimmed region: the intersection between the plane and the surface yields a trim curve, which demarcates where material is retained. The plane itself is a tool, not a physical object, though it can be used to guide manufacturing or inspection processes such as cutting, milling, or sectioning.

In practice, trimvlak operations are common during surface modeling, where complex freeform surfaces are trimmed to create clean edges, prepare parts for assembly, or define sections for analysis. Some software uses the term trim plane, clipping plane, or section plane, with subtle differences: trimming refers to removing material; clipping focuses on visibility; sectioning emphasizes cross-sections.

Etymology: from trim (to cut away) and vlak (plane) in Dutch. The exact usage and terminology can vary by software and engineering domain; some contexts may prefer trimming with curves rather than planes.