Clay allows the designers and engineers to makewithout the need for multiple drawings and accurate sketches. This is especially useful in wind tunnel testing when a small change can dramatically affect the aerodynamic efficiency of the vehicle. Renting a wind tunnel for testing can cost thousands of dollars per hour, so quick changes are necessary. The clay model not only allows for that but also extremely detailed changes with a finesse that a computer can’t match.
The first company to use clay models in its design process was General Motors in the 1930s, pioneered by. The first full-scale clay models allowed the designers to see and touch the design in three dimensions, allowing for a better understanding of the curves and shapes. Moreover, it was actually simpler and faster to build the car out of clay than to design it in a traditional way – making the panels out of steel from scratch.
Modern clay models start out with a steel frame that the wheels are connected to, with most of the shape being made of foam. The clay makes up the fine details of the outer skin, and usually has a thickness between 1-2 inches . Both clay and digital work together for the bulk of the design work by using a CNC machine to rough out the basic shape.
Clay models can cost automakers hundreds of thousands of dollars to produce, but are still a necessary part of the design process and will probably be for years to come.