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Basic dimension


In technical drawing, a basic dimension is a theoretically exact dimension, given from a datum to a feature of interest. In Geometric dimensioning and tolerancing, basic dimensions are defined as a numerical value used to describe the theoretically exact size, profile, orientation or location of a feature or datum target. Allowable variations from the theoretically exact geometry are indicated by feature control frames, notes, and tolerances on other non-basic dimensions.

Basic dimension are denoted by enclosing the number of the dimension in a rectangle.



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