Getting Started With Pro/ENGINEER Wildfire 2.0 - STROJNISTVO.com

Default datum planes and part coordinate system
Datum points and coordinate systems are both points, either fixed or
offset from a surface or vertex. Datum points can be used separately or
combined into a patterned array that behaves as a single feature. These
arrays can be saved as ASCII files and reused in other designs.
Coordinate systems are points that define an x-, y-, and z-direction. Each
part that you create is based on a coordinate system. You can use
coordinate systems within parts or assemblies to define the direction of
other components. Coordinate systems are used, for example, to define
the direction that an auto routed wire or cable will exit the connector.
Use Insert > Datum from the main menu to add datums at any time.
Specify the datum type, reference, and offset, if any. Datums that are
added to create specific features remain with the feature's section, and
they are not displayed in the 3D model. You can redefine datums by
selecting them from the Model Tree. Right-click the datum on the Model
Tree and use the Edit Definition command on the shortcut menu.
Defining Parts in Sketcher
The Sketcher is best described as a submode of Part mode that serves as
an electronic 2D drafting board within the 3D environment. You will use
Sketcher to create geometric shapes in a part. Associative details that you
build into a sketch, or section, such as geometric constraints or relations
between dimensions, act as a foundation for all other alterations to follow.
3-2 Getting Started with Pro/ENGINEER Wildfire 2.0