E-MANUFACTURING ONE-OFF INTRICATE CASTINGS USING RAPID PROTOTYPING TECHNOLOGY

There is an industrial need for rapid manufacture of one-off intricate castings, for defense, vintage equipment and medical prosthetics. This paper presents a systematic approach for this purpose, using a combination of reverse engineering, solid modeling, rapid prototyping, rapid tooling and Internet technologies. Rapid prototyping (RP) technology, involving automated fabrication of intricate shapes using a layer-by-layer principle, has matured over the last decade. Two basic characteristics of RP make it eminently suited to e-manufacturing: (1) the main input is a solid model of the part in a facetted format stored in a STL file (generated by 3D scanning an existing part or by solid modeling), and (2) the fabrication process is highly automated; no part-specific tooling is required. In practice, there are a large number of combinations of RP and RT, besides a choice of materials and fabrication equipment. These decisions greatly influence the quality of the parts (in terms of surface finish, dimensional accuracy, strength and life) as well as the lead-time and cost. The paper also presents the experimental investigations to demonstrate the methodology and benchmarking major RP/RT methods for casting application