Past, present and future. Throughout history, shoes and the materials that form them, have evolved even in totally divergent aspects: there have been used metals, leather, palm-tree leaves, wood of different kinds, embroidery and a long list of diverse materials. Regarding the height of the heels we also check notable differences: with platforms, pegs, flat, lifts, Venecian plates or the famous Louis XV shoes. But, without any doubt, design in each age is notoriously different, and in some cases, they even show a bit of unusual aggressiveness, let’s remember the Anjou footwear with the tips up, the Egyptian engraved sandals, the boots of the Middle Ages or the footwear belonging to a specific group of the population. The thing is that observing the evolution of footwear is, in some cases, to study the history of humanity.
The footwear manufacture process starts its mechanization in the last part of the 19th century, at that time there started to appear the new drill or sew or cut machines, among others, slowly moved, and the heaviest ones, with animal drawn or hydraulic forces. The appearance of the electric energy leads to a definite impulse in the mechanization of manufacture. It is in the first part of the 20th century when footwear industry experiments the definitive step from artisan industry to mass-production. In the region of La Rioja, since the 70s it was produced an important concentration of companies that dedicate their efforts to this sector, locating themselves basically in Arnedo and its surroundings. Starting with an important craftsmanship tradition, they knew how to develop an industry of first economic order for the region. There was then an industrial development that allowed factories to acquire more advanced technologies and to contribute their best products, improving the productivity.
Despite this added value, currently, the design process and footwear manufacture is an artisan procedure in which you reach the top sole through the elaboration of sketches and manual construction of prototypes. A new model or line of footwear rises from the election and redesign of the shape that will mark its final form. Modellers in footwear companies make sketches of the new products, and then, in collaboration with the shoe-maker who selects the starting shape to adapting it to the required design. Once the first prototypes are built, the new designs are expressed on them and they obtain the members of the cut (top part of the shoe) that will define the shoe.
The most complicated part in the whole manufacture process is the sole: the shape can be obtained more or less in an easy way in a sole, the materials can be cut by hand with a blade or with automatic machines, although the prototype of the sole is a much more complex procedure. In order to do so, an expert model maker starts with the sketches of de modellers and the shapes and “sculpts” the sole in a resin block. This is a laborious process that has to be made by a professional artisan and that depends on the interpretation of the sketches, because they generally don’t define exactly the measures.
Other added inconvenience that this way of manufacturing prototypes of the soles is that the result is a mock-up in a rigid material. These mock-ups are useful to validate determined aspects of design, as can be the fitting of the soles to the shape, aesthetic aspect, correct support etc. However, they have big limitations as far as the limitation in checking of the setting and other properties of the shoe.
Immediacy, save of costs and reliability in a new manufacture process of sole prototypes.
In this sense. The Technologic Centre of Footwear of La Rioja (CTCR) has occupied a relevant position in the search of innovative solutions that have allowed overcoming those inconveniences and difficulties that this industry has encountered in its way. In parallel, it gives direct services, transfers technology and knowledge and investigates in diverse lines applied to footwear manufacture, its components and its auxiliary products, related to the development of new materials and manufacture systems, just like the increasing of benefits as a finished product.
It also Works with the environmental and quality field checking the raw materials and the finished products, but, regarding what has previously said, the CTCR has been a referent in a concrete field: the one of soles and moulds, of vital importance in the zone in which is framed, due to the principal activity of the companies. It has a design workshop equipped with the most advanced machines and software of the sector, that allows to offer to the companies the most modern technology serving their needs: it has programmes that can design the sole in 3 dimensions and has a prototype machine with three-dimensional models, it can built prototypes in an agile way and reproduce them faithfully to what is done in the computer.
This machine uses a similar material to plaster or cast, so that the obtained prototypes are rigid and a bit fragile (depending on the thickness of the pieces)
As it has been previously mentioned, the prototypes in rigid materials, either obtained by traditional procedures or by fast prototypes, they have their use to validate determined aspects of design and integration with the rest of the shoe. However, it is not until the mould is built and the first samples are injected or vulcanized when it can be checked the features of the sole.
Traditional procedure of design and sole making. In this sense, it stands out one of the last innovations developed by the CTCR that has designed a manufacture quick process of the moulds for the construction of sole prototypes, in materials similar to the final ones or even in definitive materials. This service of prototypes is completely new and its start-up is allowing companies to obtain the following benefits:
a.-Reduction of the deadline and save in the process of developing new products.
b.-Competitiveness originated from the agility that introducing the new models in the market such as the footwear supposes.
c.-Presentation of themselves without a need of investing in moulds.
The procedure stars with the design in 3 dimensions of the model that i is intended to prototype, in order to make a prototype of the sole in rigid material. This is used to build on it a mould, in which prototypes of the original sole are obtained. In the CTCR for its construction it is used a new 3D printer that deposits successively layers of a material similar to plaster, at the same time that its magnetic head has a fluid that, as an adhesive, acts in concrete zones. Then, the procedure needed takes place to have the two parts in a silicone mould, caracterised by the great quality that it offers in the details. Finally, the elastic is built with polyurethane, because it is easily operable and it doesn’t require elevated temperatures nor pressures for its solidification.