Development of designs.

Development of designs

A design intended for manufacture normally develops from an initial proposal through modelling, prototyping, testing and refinement before it becomes a production product. Moving from one prototype to repeated commercial manufacture often requires changes to the design rather than simply making the prototype many times.

Types of prototype

A visual prototype communicates overall form, size, proportion and appearance and may contain no working parts.

A proof-of-concept prototype tests whether the main function, mechanism or technical principle works. Its appearance may be unimportant if the purpose is to gather functional evidence.

A production prototype closely represents the intended manufactured product in its materials, construction, appearance and function. It can be used for final testing, user trials and checks before full production.

From prototype to batch or mass production

A one-off prototype may use flexible workshop processes because there is little benefit in investing in expensive dedicated tooling. For batch or mass manufacture, designers may alter materials, wall thicknesses, joints, dimensions, tolerances and component layout so that the product can be produced repeatedly and economically.

Production quantity can justify greater use of jigs, fixtures, CNC equipment, moulds, dies, automation and dedicated assembly systems. Higher setup and tooling costs can be spread across many products, reducing unit cost.

The design may also be changed to reduce the number of parts or operations, use standard or bought-in components, simplify assembly and make quality checking easier. These changes should not compromise the specification or required product performance.

Selecting the production method

The final manufacturing process must suit the material, form, required accuracy and finish, production quantity, available equipment, labour, production rate and cost. For example, a 3D-printed polymer prototype may prove the form and fit of a design, while injection moulding could be more appropriate for high-volume manufacture of the final thermoplastic component.

A process is therefore appropriate when it can achieve the required product consistently at the intended scale. The method that works for a prototype is not automatically the best method for commercial production.