Rapid manufacturing (RM) is a modern production method based on layer by layer manufacturing directly from a three-dimensional computer-aided design model. The lack of tooling makes RM economically suitable for low and medium production volumes. A comparison with traditional manufacturing processes is important; in particular, cost comparison. Cost is usually the key point for decision making, with break-even points for different manufacturing technologies being the dominant information for decision makers. Cost models used for traditional production methodologies focus on material and labour costs, while modern automated manufacturing processes need cost models that are able to consider the high impact of investments and overheads. Previous work on laser sintering costing was developed in 2003. This current work presents advances and discussions on the limits of the previous work through direct comparison. A new cost model for laser sintering is then proposed. The model leads to graph profiles that are typical for layer-manufacturing processes. The evolution of cost models and the indirect cost significance in modern costing representation is shown finally.

DOI: 10.1243/09544054JEM894Abstract: Rapid manufacturing (RM) is a production method able to build components by adding material layer by layer, and it thus allows the elimination of tooling from the production chain. For this reason, RM enables a cost-efficient production of low-volume components favouring the customization strategy. Previous work has been developed on costing methodologies applicable to RM, but it was limited to the scenario of the production of copies of the same part. In reality, RM enables the production of different components simultaneously, and thus a smart mix of components in the same machine can achieve an enhanced cost reduction. This paper details this concept by proposing mathematical models for the assignment of the full production cost into each single product and by validating through a case study. This paper extends previous work on RM costing by adding the scenario of simultaneous production of different parts.

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -The purpose of this paper is to outline how rapid manufacturing (RM) could influence the decision-making process for managers involved in make or buy decisions. Design/methodology/approach -A literature review on make or buy issues has been carried out and the results of which have been distilled into a number of qualitative considerations. These considerations have been formed into three possible make or buy scenarios: the firm has no experience of rapid prototyping (RP) or RM; the firm already has an RP department; and the firm already has an RM function. In order to analyse the decision further a quantitative approach has been taken, mainly adapted to the last scenario but applicable also to the second scenario. Here, manufacturing cost data has been directly compared with price information from two current RP bureaus. The differences between RM cost and RP price have been studied. Findings -Strategically, the points analysed were in favour of the make option. Economically, the lack of dedicated RM bureaus and the consequent use of RP costing has further pushed the make or buy decision in favour of make. Originality/value -There is a lack of work on the implementation of RM as a mainstream manufacturing process. Existing knowledge has begun to look at the use and costs of RM, however, this paper highlights the lack of dedicated RM providers.

This paper presents work on the development of a build time estimator for Rapid Manufacturing (RM). A time estimator is required in order to develop a comprehensive costing tool for RM. An empirical method has been used to estimate build times utilising both simulated and actual builds for a Laser Sintering (LS) machine. The estimator presented here is based upon object geometry and therefore the fundamental data driving the model is obtainable from current three dimensional Computer Aided Design (3D-CAD) models. The aim of the paper is to define a model describing the build times for a laser sintering machine either for single or multiple objects.