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Selective laser sintering can be used to manufacture injection mould inserts using an indirect metal laser sintering process, such as the RapidTool™ process commercialised by 3D Systems. The volume of material to be laser processed for insert manufacturing is very high when compared to that for plastic prototype manufacturing. Consequently, the time involved in the laser processing is also very long. This paper describes the development and assessment of shelling strategies to be applied in an indirect rapid tooling process aimed at reducing time in the process. The feasibility of the shelling idea has been confirmed and although the scanning system offers some limitations to the idea two strategies are presented as successful, open shell and closed shell, with a great potential to save time.

The purpose of this paper is to identify the key elements of a new rapid prototyping process, which involves layer‐by‐layer deposition of liquid‐state material and at the same time using an ultraviolet line source to cure the deposited material. This paper reports studies about the behaviour of filaments, deposition accuracy, filaments interaction and functional feasibility of system. Additionally, the author describes the process which has been proposed, the equipment that has been used for these studies and the material which was developed in this application.

The research has been separated into three study areas in accordance with their goals. In the first, both the behaviour of filament and deposition accuracy was studied. The design of the experiment is described with focus on four response factors (bead width, filament quality, deposition accuracy and deposition continuity) along with function of three control factors (deposition height, deposition velocity and extrusion velocity). The author also studied the interaction between filaments as a function of bead centre distance. In addition, two test samples were prepared to serve as a proof of the methodology and to verify the functional feasibility of the process which has been studied.

The results show that the proposed process is functionally feasible, and that it is possible to identify the main effects of control factors over response factors. That analysis is used to predict the condition of process as a function of the parameters which control the process. Also identified were distances of centre beads which result in a specific behaviour. The types of interaction between filaments were analysed and sorted into: union, separation and indeterminate. At the end, the functional feasibility of process was proved whereby two test parts could be built.

This paper proposes a new rapid prototyping process and also presents test studies related to this proposition. The author has focused on the filament behaviour, deposition accuracy, interaction between filaments and studied the functional feasibility of process to provide new information about this process, which at the same time is useful to the development of other rapid prototyping processes.

The aim of this work is to study the influence of the quality (surface profile) of the support base on dimensional accuracy in the Z-axis in fused deposition modeling (FDM).

The surface profile of a support base produced using a standard (default) FDM configuration is analyzed experimentally, and two new deposition configurations are proposed. Some parts are built using these approaches, and the influence of the profile on Z accuracy is investigated. The parts are examined using a contact method and measured using a caliper.

The surface profile of the support base has a direct influence on FDM part accuracy in Z. The results show that the accuracy in the Z dimension of an FDM prototype can be increased by improving the surface quality of the support base. In cases where accuracy is paramount, this can be achieved by better planning (tuning) of the support strategy.

A significant component of the Z error in FDM has been identified and studied.

One major problem preventing further application and benefits from additive manufacturing (AM) nowadays is that AM build parts always end up with poor geometrical quality. To help improving geometrical quality for AM, this study aims to propose geometrical deviation identification and prediction method for AM, which could be used for identifying the factors, forms and values of geometrical deviation of AM parts.

This paper applied the skin model-based modal decomposition approach to describe the geometrical deviations of AM and decompose them into different defect modes. On that basis, the approach to propose and extend defect modes was developed. Identification and prediction of the geometrical deviations were then carried out with this method. Finally, a case study with cylinders manufactured by fused deposition modeling was introduced. Two coordinate measuring machine (CMM) machines with different measure methods were used to verify the effectiveness of the methods and modes proposed.

The case study results with two different CMM machines are very close, which shows that the method and modes proposed by this paper are very effective. Also, the results indicate that the main geometrical defects are caused by the shrinkage and machine inaccuracy-induced errors which have not been studied enough.

This work could be used for identifying and predicting the forms and values of AM geometrical deviation, which could help realize the improvement of AM part geometrical quality in design phase more purposefully.