Chapter 3 Datums 95 The Fixture Setup (Enlarged View) The Drawing Locating pins Datum plane X Datum feature Part X3 X1,X2 Example 3-20. Datum target points on a drawing and the points established with locating pins. When datum target points are used on a drawing to identify a datum plane, the datum plane is established by locating pins at the datum tangent points as shown in the magnified representation in Example 3-20. The locating pins are rounded or pointed standard tooling hardware.