Rapid tooling approaches for small lot production of sheet-metal parts

Using Rapid Prototyping Techniques (RPTs) like Stereolithography or Selective Laser Sintering, the automotive industry produces plastic parts for prototypes faster and cheaper compared to the techniques used up to now. As a consequence of this process, the automotive industry increasingly demands to have sheet-metal parts also earlier than now at their disposal. This paper deals with rapid prototyping (RP) process chains to manufacture large sheet-metal forming tools. It gives an overview of technically possible solutions. After that, the paper deals more in detail with two of the approaches, namely layer milling and resin casting. It describes these manufacturing methods and presents the result of a case study which compares the approaches with the actually used production method.