To Create a Datum Plane
1. Click Create > Datum Plane. The Datum Plane dialog box opens.
2. Select a reference in the graphics window such as a surface, vertex, curve, datum axis, or an edge. The selected references appear in the References collector in the Datum Plane dialog box.
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To add more references, hold down the CTRL key and select the required referenced in the graphics window.
Select the constraint type in the adjacent to the selected reference in the References collector.
If the selected references are not sufficient to create the datum plane, you must select additional references until the datum is fully constrained.
3. To adjust the outline display of the datum plane, click Adjust outline in the Display tabbed page.
4. To adjust the size by specifying the width and height of the datum plane, select Size in the Display tabbed page and specify values for Width and Height.
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The width and height values for the outline display of the datum plane are not visible in the graphics window.
Dimension outline handles are displayed at each corner of the datum plane preview. You can drag one of the handles to change the width or height of the datum plane.
To maintain the proportion of the width and the height of the datum plane, click Lock aspect ratio in the Display tabbed page.
5. To adjust the size by specifying a reference, select Reference in the Display tabbed page and select a reference such as a surface, edge, or axis in the graphics window.
6. Click OK in the Datum Plane dialog box to create the datum plane. The datum plane appears in the graphics window and also appears as a separate node on the GTS Tree.