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The purpose of this paper is to investigate a method for comparing the scanning and reproducing accuracy of highly shaped objects like plaster casts used in dentistry.

Theoretical considerations on errors introduced by the scanning systems and subsequent point clouds data elaboration have led to a method to estimate the accuracy of the whole process. Suitable indices have been chosen and computed at each stage. As a final result, the overall chain, scanning and reproducing systems can be assessed. In order to validate the proposed method casts have been scanned by means of commercial systems and then reproduced by using different rapid prototyping technologies, materials and parameters. Error indices have been computed and reported.

Since it is not possible to define reliable and meaningful reference models for non‐standard shapes, an absolute accuracy value for the scanning process cannot be stated. Anyway the proposed method, thanks to relative performance indices, allows the comparison of different acquisition systems and the evaluation of the most performing manufacturing chain.

The study provides a method to assess the relative performance between commercial systems both in scanning and reproducing stage.

In literature, some studies on the accuracy of scanning devices have been found but they are based on standard geometrical features. In this paper, the problem of complex shapes in absence of reference model is addressed instead.

High pressure die casting is a widely used industrial process to manufacture complex-shaped products in light alloys. Virtual prototyping techniques, especially numeric-based simulations of the casting process, allow the die filling process to be evaluated and help faster optimization of the gating system, which is the most critical element of the mould. The purpose of this paper is to present a four step approach to design optimal moulds taking advantage of the simulation tools.

No formalized method to design an optimal gating system is available yet and the majority of the studies aim to optimize existing geometries or to choose from alternative solutions. Rather than optimizing the geometries of predefined designs by running attempt trials, the proposed approach defines a procedure to position cavities, gating systems and, finally, to determine the whole mould geometry.

The approach is demonstrated through three different industrial applications. The design of a six-cavity mould for gas cooking burners is reported at first. Then, two test cases, a cup and a radiator, are reported for showing different arrangements of the gating system. The reached quality of the mould design has been assessed using metallographic analyses of the casts.

The design of a mould is strictly correlated to its product and mainly based on a trial-and-error approach. Numerical simulations offer a powerful and not expensive way to study the effectiveness of different die designs and filling processes. The paper proposes a structured approach for the definition of the gating system. It ultimately leads to improvements in both product quality and process productivity, including more effective control of the die filling and die thermal performance.