Creating center lines

A center line is an associative linear entity drawn between two lines or two linear segments of polylines. The center line is drawn using the apparent midpoints between the two start points and the two endpoints of the selected lines or segments. If selected lines or segments are not parallel, the center line is drawn using the intersection pointreal or imaginaryand the midpoint between the endpoints of the selected lines.

To create a center line

   1   Do one of the following to choose Center Line ():     

    On the ribbon, choose Annotate > Center Line (in Center Lines).

    On the menu, choose Dimensions > Center Line.

    On the Dimensioning toolbar, click the Center Line tool.

    Type centerline and then press Enter.    

   2   Select the first line or linear polyline segment.

   3   Select the second line or linear polyline segment.

If specifying linear polyline segments, only the segment you pick, not the whole polyline, is used to calculate the location of the center line.

You can change the appearance of center lines.
To change the appearance of existing center lines, use the Properties pane or grips. To change the appearance of new center lines, before you draw them modify the CENTERLTYPE, CENTERLTSCALE, and CENTEREXE system variable values.