Preceding the production of a prototype automobile, designers will frequently construct a model of the concept car's design using foam and foam board. This allows them to work with a scaled-down version of the car and easily tweak aspects of the design. Building your own prototype car body design using foam board can help you bring physical form to your design ideas and inspirations.
Print out a copy of the design plans for your prototype car. These could be granular designs drafted using a specialised software program or simple design specs you've assembled on your own. You will use the design specifications to guide the creation of the foam board prototype.
Determine the scale and size of the model car body that you wish to build. You can divide the actual proposed dimensions of the car by a number, such as 24, to get the dimensions for a 1:24 scale model. Write down these scaled-down measurements as you will need them in the upcoming steps.
Using the ruler and pencil, outline the different body panels that you will need on a flat piece of foam board. Use the scaled-down dimensions to define the sizes of each foam board body panel.
Cut the body panels out of the foam board by running the razor blade around the outlined edges that you marked using your pencil in the previous step. Set each body panel aside and label it, if you feel necessary, as you work through the piece of foam board.
Construct the prototype car body out of the foam board by assembling the different pieces, using the original design sketch to guide you, and securing them together using light coats of rubber cement. Start constructing the model car body using the largest pieces, such as the roof, and working your way down to the point where you can integrate smaller and more granular design aspects into the prototype.