Tipster Danny Korem uses parametric constraints in AutoCAD to assist his design process. Here, he shows us how to convert dimensions into dimensional constraints.
"This tip takes full advantage of the development of dimensions through the years. At first, associative dimensioning dealt with defpoints, then the associativity created a link between the object and the dimension. Now one can transform an associative dimension into a parametric one. By doing that, you might edit your geometry by editing the dimensions! It's great if you can master these capabilities.
"For best results, use the Infer Constraints function located at the lower-left corner of your AutoCAD screen (that means your geometry will react to parametric dimensions later on). In order to use your dimensions, they should be associative (that means if you did not alter the defaults, they are). When a dimension is selected, look at its Properties (or Quick Properties); the value of Associative must be Yes.
"Now you will need some constrained geometry and a few dimensions attached to it. In the Parametric ribbon tab, click on the Convert icon. Select the dimensions you would like to turn into parametric dimensions. The result will look like the image below. To edit the geometry, double-click a dimension and replace the current value with a new one. Enjoy!"
Notes from Cadalyst Tip Patrol: If you aren't using parametric constraints in AutoCAD, I suggest you give them a try. Parametric constraints are a way of programming your linework.
Constraints define the way geometry interacts with each other. In AutoCAD, there are two types of constraints: Geometric and Dimensional. Dimensional constraints can be created in two ways: by converting associated dimensions, as described in this tip, or by using the dimensional constraint tools. The tools create dimensions in the same way a dimension tool does, except the linework is constrained. Geometric constraints define the geometric relationship between two objects. For example, a parallel constraint will keep two lines parallel. Inferred constraints automatically apply geometric constraints as you create geometry. This can help you to save time and make sure your linework is correct.