Toolmaking specialist manufactures one-to-one prototypes from PA6.6-GF30
Prototypes can be produced in many different ways. 3D printing is a common method of producing prototypes. A distinction can be made between three main plastic processing methods. Fused Deposition Modeling (FDM), stereolithography (SLA) and selective laser sintering (SLS). The advantage of these methods is that prototypes can be produced relatively quickly and cost-effectively. The limited choice of materials as well as the strength-reducing circumstances of the layer-by-layer build-up represent the main disadvantages of these methods. Often the prototypes and the final article are made of different materials. 3D-printed prototypes can therefore usually only assume the role of an illustrative model.
What if you want to have a visual sample, but also to carry out tests with the prototype? And this already in the A- or B-pattern variant.
There is currently no 3D printing process that can produce prototypes with the same properties as an injection-moulded component. Prototypes are usually produced from common industrial plastics such as glass-fibre reinforced polyamide (PA6.6-GF 30) or polyoxymethylene (POM). This is done using prototype moulds, which are fitted with complex metal mould inserts. This manufacturing process is very cost intensive and time-consuming. As an expert for special machines and tool construction, VWH GmbH dealt with this problem and developed a possibility to produce prototype moulds faster and more convenient.
The company from Herschbach Oww. is the contact for national and international customers from different industries and offers a wide range of different plastic injection moulds as well as individual tool solutions from first prototypes and small series up to mass quantities. As a general contractor, VWH GmbH supports its customers from article design through series production to article packaging.
"Our goal behind the optimization of prototyping was to make injection molded prototypes of POM, PA6.6-GF 30 or similar materials available to customers within five working days," says Andreas Klatt, Technical Manager at VWH GmbH. In order to achieve this goal, various tests were carried out in the company's own technology centre for plastics. The high processing temperatures of the respective plastics and the necessary surface requirements for the cavity presented themselves as the biggest task to be solved. A particular sticking point was the heat dissipation of the article via the mould cores.
After numerous tests of several materials and process approaches, a combination was finally successful. A hybrid construction consisting of plastic mould cores with metal parts for heat dissipation was developed. Thus, it is now possible to produce prototypes from POM, PA 6.6-GF30 and similar materials within a very short time and at optimised costs. In addition an existing master form is used and the form cores can be manufactured by means of 3D pressure. With the internal injection moulding machines the prototypes are moulded afterwards. Subsequent changes to the prototypes can be implemented quickly, easily and cost-effectively, as the printed cores can be reprinted within a few hours.
In this way, VWH GmbH enables its customers to quickly obtain prototypes with which they can carry out proper functional tests. The quality of the A- and B-samples could thus be improved many times over.
