Define Datum References for Geometric Tolerances
1. Select the geometric tolerance instance, the Geometric Tolerance ribbon appears.
2. Under the
Tolerance & Datum group, define the
Primary,
Secondary, and
Tertiary references as necessary. The lists contain the currently selected datum and all other datums in the current geometric tolerance model. Click
![](../detail/images/sel_pick.png)
to select another set datum or axis.
| To select a set datum plane or an axis contained in an inheritance feature, click ![](../detail/images/sel_pick.png) and select the required set datum plane or the axis on the Model Tree or in the graphics window. |
3. To define a composite tolerance, click Composite Frame. Type a tolerance in the Value box and select the desired datum from the Datum reference list:
◦ Primary
◦ Secondary
◦ Tertiary