Use the Centerline command to construct Centerlines. You can set the extension for Centerlines to exceed the entities which define the contour.
The specific LineStyle for Centerlines is assigned automatically.
Centerlines are created between pairs of Lines, Arcs, and PolyLine segments.
Linear contours need not be parallel; the resulting line represents a bisecting line in this case. The two entities can be of different lengths.
Selected pairs of Arcs must be concentric.
You can create Centerlines continuously in one command. When you select pairs of PolyLine segments one after the other, the resulting centerline segments are joined to one entity, whereas each pair of lines or arcs creates separate Centerlines.
The Centerline represents an entity of its own.
To construct Centerlines:
The Centerline is created between the pair of entities.
To undo the previously created Centerline, specify the Undo option.
To set Centerline extensions:
The default value is 0.25 (if you use an ANSI-based template drawing) or 2.5 (if you use an ISO-based template drawing) drawing units.
Note: Use EntityGrips to modify the length of Centerlines which preserves their orientation.
Access
Command: Centerline
Ribbon: Home > Annotations > Centerline
Menu: Draw > Centerline