You can position a datum point by selecting a point on the model and entering the X-, Y-, and Z-coordinates of an offset from the point.
To create a datum point at an offset from a selected point:
From the main menu bar, select Tools
Datum.
The Create Datum dialog box appears. The dialog box outlines the types of datum geometry you can create.
ABAQUS/CAE displays prompts in the prompt area to guide you through the procedure.
Tip:
You can also create a datum point using the 
tool, located in the module toolbox. For a diagram of the datum tools in the toolbox, see “Using the Datum toolset,” Section 40.2.
From the list of types at the top of the dialog box, choose Point.
The Method list indicates the methods you can use to create a datum point.
From the Method list, select Offset from point and click OK.
From the part or assembly in the current viewport, select a point.
In the text field that appears in the prompt area, enter the X-, Y-, and Z-coordinates of the offset from the selected point.
The datum point appears. You can modify the coordinates of the offset by selecting FeatureEdit from the main menu bar and selecting the datum.
