Defining a Coordinate System

From the Feature section of the action bar, click Coordinate System

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In the Coordinate System dialog box, click Select Point and select a vertex from the work area to define the origin of the coordinate system.

Select an edge from the work area to define the direction of the X axis.

Select a face from the work area to define the direction of the Y axis.

Note: The Y axis of the triad aligns normal to the face you select. The direction of the Z axis depends on the positions of X and Y axis.

Click

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