Development of transfer type variable lamination manufacturing (VLM-ST) process

Abstract

RP technologies have been widely used to reduce the lead-time and development cost of new products. However, most of the developed RP technologies have disadvantageous characteristics, due to their working principle: a large building time, a stair-stepped surface of a part and additional post-processing. In addition, it requires a high cost to install, operate and maintain the RP apparatus. The objective of this paper is to propose a new rapid prototyping system, transfer type variable lamination manufacturing process using expandable polystyrene foam (VLM-ST), to overcome the disadvantages. VLM-ST has various technical novelties such as a thick layer with thickness of less than 4 mm, a sloped surface with the first order approximation between the top and bottom surfaces of each layer, a stacking method using the pilot pin and building board, a concept of unit shape layer (USL), and a synchronized four-axis hotwire cutter with linear heat source and a parallelogram mechanism. In this paper, the characteristics and the key features of VLM-ST are discussed. In order to investigate the applicability of the new RP process, various prototypes, such as an extruded shape, son-o-kong shape, a world-cup logo, and a human head shape, are manufactured by the prototype of the VLM-ST apparatus. All shapes are manufactured within one hour. In addition, the efficiency of the new RP process is examined by comparing the world-cup logo shape and the human head shape with those of Laminated Object Manufacturing (LOM) from the viewpoint of geometrical conformity, total building time, building cost, and dimensional accuracy. (C) 2002 Elsevier Science Ltd. All rights reserved.