Designers use many techniques to create products and solve problems. Design and development involve creating working drawings and parts lists to enable a third party to manufacture the design.
Modelling and prototyping to help with the design process
Modelling can be time-consuming and expensive, but a physical model allows a person to see and handle a product unlike viewing it on a screen through computer aided design (CAD). Computer aided manufacture (CAM) models made on a 3D printer using a CAD drawing are very accurate but also expensive, time-consuming and limited to 3D-printable materials. Product designers can use easy-to-form and easily accessible materials, eg balsa, jelutong and cardboard, to create cheap models quickly and cheaply.


Quick textile designs can be modelled out of newspaper and more detailed models can be made from cotton or calico. Fabric models are called toiles and can be made on a mannequin to test the dimensions and drape of a garment.
Breadboards are used in the early development of electronic products. They are boards containing a series of holes that electrical components can be pushed into to allow current flow without making a permanent join. Components can then be easily swapped to improve or fix a circuit.

| Advantages of physical modelling | Disadvantages of physical modelling |
|---|---|
| Allows a designer to physically handle a design and view from all sides | Can be time-consuming and complicated |
| Changes can be made quickly and easily | 3D printed models can be expensive and have limited materials available |
| Materials such as cardboard can be found cheaply and easily | Models can’t generally be used for testing as they don’t use the same materials that the product will be made of |
| Models can be scaled up or down in size | |
| Models can be used to show to a client and get feedback on before production |