Firming designs: rapid prototyping

Although modern CAD packages can give a very good idea of what a finished part will look like, there is still no substitute for a tangible model. Most modern computer-aided design (CAD) systems have excellent shading and animation features, but there is no substitute for a physical solid model to establish the feel of a product. Various analysis techniques can only be applied with a physical part: a good example is in examining the detailed flow of gas or fluid around the part, which is extremely difficult to model accurately by computer. This is where rapid prototyping and tooling can give the manufacturer an edge. If the part needs modification, the designer can alter the CAD data and produce a second model as quickly as the first. The author discusses some techniques