AutoCAD® 2012 FOR DUMMIES®

Is 3D for Me?

Traditional 2D drawings provide clues to help the viewer's mind construct a 3D model from the 2D image on paper. Multiple views from different viewpoints in 3D space give experienced designers, drafters, and builders the information they need to make 3D sense of 2D drawings. Design and drafting have succeeded pretty well by using 2D representations as the guide to creating 3D objects. But at some point, nothing can replace a true 3D model, such as in helping someone understand how a building will look when constructed or how two parts fit together.

What does using 3D in AutoCAD mean? Fundamentally, it means creating models instead of drawings. Rather than generate cross sections of an object or individual views of it from certain perspectives, you create a three-dimensional model of the object. This 3D depiction of each object includes all the necessary information for AutoCAD to create a drawing view from any point of view. With a properly constructed 3D model, AutoCAD can output commands to machines to create actual 3D objects, whether plastic prototypes carved from a tank of jelly by 3D printers, or an actual bolt, valve, or piston created by computer-controlled machine tools.

As I explain in Chapter 21, AutoCAD can create three types of 3D models: Wireframe, Surface, and Solid. In most practical applications of 3D, you select one of these types for all or most of the objects in the drawing, based on ease of construction and intended use of the model. However, ...