Redesign and cost estimation of rapid manufactured plastic parts

The purpose of this paper is to highlight how rapid manufacturing (RM) of plastic parts combined with part redesign could have positive repercussion on cost saving.

Comparison between two different technologies for plastic part production, the traditional injection molding (IM) and the emergent RM, is done with consideration of both the geometric possibilities of RM and the economic aspect. From an extended literature review, the redesign guidelines and the cost model are identified and then applied to a component selected for its shape complexity. It is an assembly that was redesigned for RM purpose, in order to take advantage of additive manufacturing potentialities. The geometric and economic differences between IM and RM are discussed.

This research evidences that currently in Western Europe RM combined with redesign can be economically convenient and competitive to IM for medium volume production of plastic parts. Consequently, this is a great opportunity to keep the production in Europe instead of moving it overseas.

As regards manufacturing costs, results presented in this study are mainly based on cost estimation provided by Italian companies and it is assumed that the plant is located in Western Europe.

The research assesses the feasibility of making functional and operational plastic parts without the use of traditional manufacturing processes by redesign for RM.

Two different kinds of research papers comparing RM and IM exist in literature: on the one hand, the two techniques are evaluated from the economical point of view, on the other, the part redesign is analyzed. No paper considers the interrelation between redesign and cost estimation. In this work, these aspects are combined to point out that a remarkable cost reduction is obtained when the component shape is modified to exploit RM advantages.