Creating a Simple Datum

This task shows you how to create a simple datum on a surface. 

Datum elements are involved in geometric tolerancing specifications. For instance, when specifying an orientation or a position tolerance, you need to refer to datum elements for the specification. 

  1. Select the attachment surface to be specified as datum.

  1. Click the Datum Element  in the Annotations toolbar.
    Datum Feature Creation dialog box that appears displays "A" as the default identifier.

     

    The Tools Palette is displayed according to the type of face selected depending on the canonicity. In this scenario the Tools Palette is not used. For more information, refer to Propagating Geometry Selection for Feature Creation.

  1. Click OK to create the datum if the identifier corresponds to your choice.
    The datum feature is created in a specific annotation plane.
    The Datum entity is added to the specification tree.
    The datum is a 3D annotation without any semantic link to the geometrical tolerancing.

The display of this datum label corresponds to the ANSI normative reference.
 

  1. Select the datum and drag it. You can notice that it remains in the annotation plane.