AutoCAD FAQ

This issue is one that is more about personal preference. Dimensioning should be done in whichever area is more comfortable.

Those members of this forum who recommend dimensioning in Paper Space do so for the following reasons:

• The model stays clean of lines.
• It eliminates the need for hiding dimension layers in different views.
• With associated dimensions turned on there is no worry about the scaling aspect of the drawing.
• If drawing in 2d, the points stay associated, so if an object is stretched the dimension goes with it.

There would be just as many members of this forum who prefer to dimension in Model Space for the following reasons:

• Changing the scale of the viewport leaves the Paper Space dimensions out of position.
• Stretching or resizing an object in Model Space leaves the Paper Space dimensions out of position.
• Moving a viewport to another location in Paper Space leaves the Paper Space dimensions out of position.

However, the above reasons for dimensioning in Model Space are negated if the dimensions are associative.

To make dimensions associative go to menu ToolsOptionsUser PreferencesAssociative Dimensioning and tick "Make new dimensions associative".



 

Associativity of dimensions is also controlled by the system variable DIMASSOC.

The settings are:

0 - Creates exploded dimensions objects. There is no association between the various elements of the dimension. The lines, arcs, arrowheads, and text of a dimension are drawn as separate objects.
1 - Creates non-associative dimension objects. The elements of the dimension are formed into a single object. If the definition point on the object moves, the dimension value is updated.
2 - Creates associative dimension objects. The elements of the dimension are formed into a single object, and one or more definition points of the dimension are coupled with association points on geometric objects. If the association point on the geometric object moves, the dimension location, orientation, and value are updated.

It is considered by many members of this Forum to be bad drawing practice to explode dimensions.

The check box "Make new dimensions associative" can only set variable values 1 or 2. Ticking the check box sets the variable value to 2.

In formats previous to AutoCAD 2002, the variable for associative dimensions is called DIMASO. This can be set to OFF or ON.

If a drawing is saved back to a format previous to AutoCAD 2002, the setting of the DIMASSOC is saved. When the drawing is opened in AutoCAD 2002 or a later version, the settting is restored.

If a drawing that was created in an earlier version than AutoCAD 2002 is opened in AutoCAD 2002 or a later version, the DIMASSOC variable takes on the value of the DIMASO variable.