May 5, 2009
Basic Dimension – GD&T Defined
Basic dimension: A basic dimension is a numerical value used to describe the theoretically exact size, profile, orientation, or location of a feature or datum target. Basic dimensions are used to define or position tolerance zones. Title block tolerances do not apply to basic dimensions. The tolerance associated with a basic dimension usually appears in a feature control frame or a note.
The Basic Dimension has a box around the dimension. The title block tolerance does not apply to basic dimensions. The tolerance associated with a basic dimension usually appears in a feature control frame or a note. And its usually toleranced with gage-makers’ tolerances. And also the true position of a feature should be established by basic dimensions.
