Tip 2222: Adjust Polyline Width
To use Adjust Polyline Width by Brian Benton, which sets the width of a polyline and scales it accordingly, load the LISP code and type the name PLWS at the command prompt to start the edit utility. The first order of business is to type in the new width value you want to apply to the polyline. Next, select the polyline and the width changes. This utility is another great example of how you can streamline drawing cleanup and edit work with LISP in AutoCAD.