Datum feature

Purpose#

Places a datum feature per DIN EN ISO 1101: a triangle on the element, a connecting line and a box with the datum letter. Datum features are the basis of the feature control frames, which refer to them in the fields primary, secondary and tertiary. Connections: Feature control frames and datum features.

Access#

• Ribbon: group Annotate, list of the split button Dimension, entry Datum Datum feature (6 in the picture at Dimension).
• Classic toolbar: list of the split button Dimension, entry Datum feature symbol.
• Command search : type Datum.

Status bar on start: Datum feature: click point on the element (use snap)….

Procedure#

1. Click the foot point on the element (with snap). The direction of the element at this spot sets the orientation: the triangle stands perpendicular on the element, the connecting line leaves at right angles. The next free letter is assigned automatically (A, B, C …; free gaps are filled first). Status bar: Datum feature A: click position of the box (ESC cancels).
2. The box hangs at the pointer; place it with the second click (Datum feature A placed).

The datum feature is bound to the element and moves with it when the element is moved. It lies on the system layer Dimensions and takes the text height of the dimensioning.

Options#

Double-click on a datum feature opens the Datum feature dialog:

After renaming, the program checks whether feature control frames still use the old letter and warns: Warning: datum A is still used by tolerance frames. The same warning appears when a datum feature is deleted.

Keys#

The command has no shortcut key.

Related commands#

• Feature control frame Feature control frame — uses the datums
• Send to back Dimensions to back — also puts datum features on the lowest Z level