Example 1: Using Primary Axis
This example shows creating a reference coordinate system by using the Primary Axis option.
To create a Ref Csys for measuring the little cylindrical slot shown above, do the following:
1. Create a reference for the coordinate system by measuring the two planes and constructing an Intersect line.
2. Click > 
Reference Coordinate System. The REF CSYS dialog box opens.
Reference Coordinate System. The REF CSYS dialog box opens.3. From the Parent Csys drop-down list, select MACH CSYS.
4. Select Primary Axis from the Transform Type drop-down list.
5. Click Orientation to open the Orientation sub-tab.
6. Select X Axis from the Align Csys drop-down list.
7. On the Graphics window, select the Constructed line.
8. Select Flip to flip the direction of the arrow, and then click Okay.