By John Flanagan
Built-In Dimension Command
There is a built-in command that can Split Dimensions with just one click. To learn how to use it, follow these simple steps:
In the example below, draw a linear dimension in the normal way for the 1800mm double door opening.
Select the Smart Dimension tool, it is located on the Annotate ribbon, under the Dimensions tab or you can type DIM on the command line.
Next, draw a dimension for the split (left side of door to centre of door) and place it over the dimension to be split.
AutoCAD will ask you to Specify how to handle the overlapping dimensions. From the options list choose Break Up.
As you can see, Break Up splits the existing dimension into two dimensions and arranges those dimensions into a continued dimension type.