AutoCAD 2008 User's
Guide > Annotate
Drawings > Dimensions and
Tolerances > Create
Dimensions > Create Linear
Dimensions >
Create Dimensions with Oblique Extension Lines
You can create dimensions with extension lines that are not perpendicular to their dimension lines.
Extension lines are created perpendicular to the dimension line. However, if the extension lines conflict with other objects in a drawing, you can change their angle after the dimension has been drawn.
New dimensions are not affected when you make an existing dimension oblique.
