Creates the center mark or the centerlines of circles and arcs.
Access Methods
Button
Toolbar: Annotation tool set 
Dimensions tool group Center Mark Menu:
Dimension
Center Mark
Summary
The default sizes of the center mark components can be set from the Dimension Style Manager, Symbols and Arrows tab, Center Marks (DIMCEN system variable).
You can choose between center marks and centerlines and specify their size when you set up the dimension style. See DIMSTYLE. You can also change center mark settings using the DIMCEN system variable.
