Once a new calibre or module has been constructed on CAD, elements are often re-produced in model form at scales of up to 20x the real size. Allowing the developers to in essence -get inside- the products on a physical level and see the interactions between the components. The approach does not replace the need for producing true scale prototypes in the final materials but saves considerable time in the development process and highlights issues which do not necessarily come to light in the virtual world. Anything can be designed but not necessarily made and assembled. Making these types of models does not require the cutters, hobbs and long programming set up times that the next stage requires in the prototyping process.
In the development process following the initial construction and models, 1:1 scale prototypes are made. Different companies take alternative approaches depending on the type of product and final numbers to be realised. For example a company planning to make one hundred thousand pieces per year will spend more time on prototyping and pre-series research than a company planning to produce a complicated calibre which will result in a single piece every month. The prototypes can be produced either using the identical machines that are used in the final production or in a mechanics workshop where the pieces are made individually. How to make the prototypes depends on multiple decisions which are effected by the type of product, numbers and the company politics. Prototypes themselves can be unfinished/undecorated examples of the final product. If this is the case then following the validation of the prototype a pre-series is made which will effectively finish and decorate the final movement to the definitive specifications but these are still in essence, prototypes. The effect of the decoration, machine or hand, may have an effect on the function of the product. Altering tolerances or simply the final aesthetic when seen on an end product may not be what was imagined on a computer screen and in the imagination. This pre-series can also be used as test pieces in the laboratory section which follows later.