SAMPLE PAGES TO BE FOLLOWED EXACTLY IN PREPARING SCRIPTS RAPID PROTOTYPING AND RAPID TOOLING IN CERAMIC AND GLASS INDUSTRY

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1 SAMPLE PAGES TO BE FOLLOWED EXACTLY IN PREPARING SCRIPTS RAPID PROTOTYPING AND RAPID TOOLING IN CERAMIC AND GLASS INDUSTRY F. Jorge Lino 1, Rui J. L. Neto 2, Ricardo Paiva 2 1 FEUP - Faculdade de Engenharia da Universidade do Porto, DEMEGI, Rua Dr. Roberto Frias, Porto, Portugal, falves@fe.up.pt 2 INEGI - Instituto de Engenharia Mecânica e Gestão Industrial, CETECOFF, Rua do Barroco, 214, Leça do Balio, Portugal, cetecoff@inegi.up.pt Abstract: In Portugal, product development in ceramic and glass industry is usually done using traditional methodologies. In most of the cases uses manual modelling, which is very slow, highly inaccurate and demands skilled persons whom are difficult to find and time consuming to train. These methodologies, highly misadjusted to the new marketing demands, tend to decrease companies competitiveness. This paper explains the work that has been done at INEGI, seeking the introduction of new methodologies in product development, using CAD 3D design or engineering tools and different rapid prototyping and rapid tooling technologies. Keywords: Rapid Prototyping, Rapid Tooling, Product Development, Ceramics, Glasses. 1. INTRODUCTION Nowadays, it is well known that new products development, particularly product modelling and prototypes production, has become quite critical in industrial performance improvement. The art of managing rapid product development depends on making good trade-offs between three possible objectives in any product development cycle: (a) development speed, (b) product cost and performance, and (c) development program expense. Ceramic and glass industry do not accept any kind of non-glass or ceramic rapid prototypes to optimise artistic design or functional geometry. Furthermore, they usually do not use any kind of rapid tooling (RT) (prototype moulds) to reduce the time to market. Important international companies worldwide have discovered that rapid product development is an enormous and relatively untapped source of competitive gain, especially for new products that have not appeared previously. During the last two years, INEGI, in partnership with some Portuguese Universities specialized in Industrial Design, namely Universidade Lusíada of Porto and Instituto Politécnico of Viana do Castelo, and some industrial companies of sanitary ceramic and decorative ceramic and glass, made some improvements in old ceramic and glass methodologies, introducing CAD 3D design tools associated with Rapid Prototyping (RP). Using RP technologies, the first (iterative) rapid tool for slip casting (casting of slurries) in plaster moulds, or ceramic or metallic moulds for glass thermoforming, pressing, static or rotative blow moulding can be made in a short period of time (Lino, et al., 2001a; Pham, and Dimov, 2001). In this paper, the authors describe their experience in the field of product development for the glass and ceramic industry, and how the CAD 3D, RP and RT technologies (for more information about these technologies, please see Lino, et al., 2001a, 2003a, 2003b; Neto, and Lino, 2002; Vasconcelos, et al., 2001; and Wholers, 1999) can be applied with success in different new products. 2.1 Ceramic Industry. 2. EXPERIMENTAL WORK A large number of CAD 3D new components were generated using different software, like Allias, Solid Works, Solid Edge and Unigraphics. Without the

2 necessity of highly specialized workers, some LOM (laminated object manufacturing) RP models were manufactured in INEGI (Lino, et al., 2001a). These first prototypes were used to evaluate the success opportunity of the new products, and some of them were presented in the International Conference USER Design, occurred in Lisbon, last March 2003 (Pereira, et al., 2003). The main reasons to produce this first generation of prototypes (see Figs. 1 to 4), were: (a) Compared with other alternatives, they are relatively cheap and fast to obtain; (b) Some design errors can be corrected according to technical limitations, namely, minimum allowed thickness, thickness distribution and geometrical corrections due to differences between the solid models and the real components; (c) Evaluation of the possibility to employ oversized prototypes as master models; (d) In all product development cases, the user has in mind a prototype production and the respective conversion in ceramic by manual casting, which is the process more difficult to control, due to the high shrinkage and correspondent distortion. Considering this, it seems that analysing and handling the prototype can dramatically accelerate product discussions and the decision about the design of the future plaster tools. Fig. 3. Painted stereolitography and LOM prototypes to simulate porcelain (design Bruno Durval). Fig. 4. Stereolitography prototypes of future ceramic parts (design Artur Costa). 2.2 Glass Industry. Some components, to be mass-produced by 3D thermoforming, static or rotative blow moulding and pressing, were designed with the aid of CAD 3D software. The prototypes of Fig. 5 were produced by LOM and painted to simulate the surface of the final glass products. Fig. 1. Natural colour and painted LOM prototype developed in INEGI. Fig. 5. LOM prototypes for appreciation of some products to be produced by glass technologies (design Anabela Alves and Ana Moreira). Fig. 2. LOM products developed in INEGI by Universidade Lusíada students (design Bruno Costa). The prototypes were painted to simulate porcelain. This prototyping procedure is not the traditional way of glassmakers evaluating new products. They only accept new prototype models in glass or crystal, which were obtained with conventional products or tools. This means that using this methodology, a considerable amount of time and money are spent just

3 for this evaluation, reducing their competitiveness and market aggressiveness. In a whole production cycle there are always some corrections to perform on the new products, because solid models are the only way to have together designers, technicians, commercials, managers and eventually the company owner s discussing about the evaluation of the probability of commercial success of the new product. After this stage, several possibilities of rapid tooling or rapid alternative processes can be used to convert the RP prototypes in glass or crystal products (Lino, et al., 2001b; Silva, et al., 2001b). Different methodologies were applied for this purpose: a) Manufacturing ceramic block moulds (Duarte, et al., 2002) for thermoforming 3D components. The traditional fibre plate cut with the adequate geometry only allows the production of glass parts with the 2D thermoforming. This is an INEGI process that can also be used for blow moulding and pressing processes, but just for 5-10 prototypes production. Fig. 6 presents some of these glass prototypes. Fig. 7. Colour glass prototypes produced by the lost wax pate verre process. Fig. 8. Aluminium sand cast mould produced from a LOM pattern. 3. RESULTS Fig. 6. Prototypes produced in block ceramic moulds by glass thermoforming, pressing and static blowing (design Joana Osório and Atlantis). b) Manufacture of glass or crystal prototypes using the lost wax process associated with the plaster block moulding. This is a very old process employed in the duplication of complex sculptures, known as pate verre process. It but that can be very interesting for prototypes conversion in glass products in a relatively cheap and fast way, allowing the new glass or crystal products acceptation before the manufacture of the future metallic production tools, which are very expensive. Fig. 7 shows some colour glass products manufactured using this technology. c) Manufacture of the final aluminium production tools (see one example of these tools in Fig. 8), which starts with the 3D design of the tools, followed by the LOM prototype of the tool and the conversion of this LOM in metal by sand casting or lost LOM technique (Lino, et al., 2001b). This process can be faster and more accurate than the traditional manual pattern making that is still used in this sector, in the same way as some decades ago. 3.1 Ceramic Industry. Rapid plaster tooling, for components production, was employed using three different approach methodologies, in order to try to evaluate the more adequate and economic processes: Moulds made by casting plaster on oversized prototypes (a); LOM match plates of the negatives of plasters moulds (b); LOM moulds to be converted in Masters using silicone rubber (c). (a) Using oversized vacuum epoxy infiltrated and painted prototypes with an as ceramic finishing, the technical approach only slightly reduces the necessary time to manufacture a porcelain functional prototype. For non-complex geometries, this approach seems to be good enough to change the old methodologies, maintaining the necessity of the skilled experienced technicians. In this case, if the first iteration gives the desired final geometry, the final mass production tooling can be produced using the first CAD 3D file, added to match plates, that can be very quickly obtained by CAM and present a fine

4 geometry and adequate dimensional quality. Fig. 9 shows plaster moulds obtained with this methodology. In this case the prototype rapid tool was also used for mass production, because the thickness and the final geometries were good enough for this type of production. 3 silicone rubber negatives of the moulds were made in order to have a durable production tool to produce large series of production plaster moulds. Although these moulds are rapidly obtained at low cost, they are not adequate to make silicones, due to some distortion problems and imprecision on the surfaces parting lines and lack of sharp edges. Therefore, it can be concluded that the process is specially indicated for short deadlines, however, with limited precision. Fig. 9. Plaster moulds of a table centre obtained by direct casting the plaster over the oversized painted LOM prototypes (design Anabela Alves). b) For a soup plate, two match plates were manufactured after CAD 3D Boolean operations, which consist in the addition of the positive of the interior and the negative of the exterior to the two plates. The resulting match plates were not good enough to mass production, but moulds production is very fast, with the advantage of not requiring specialized labour. This solution is not cheap but is faster than the first approach. After the functional prototype production, CAM match plates can be obtained with the low risk of demanding a new iteration. Figs. 10 and 11 show the tools obtained with this process. The impregnation of the match plates was adequate for LOM to support the action of the plaster water; however, the fine details and edges were not good enough to use the tool in mass production. Fig. 11 Plaster mould directly casted over a LOM match plate. This design methodology, very attractive for machined CNC master moulds, does not need skilled workers, but is too expensive due to the volume of the LOM models. Parts obtained with this procedure can be observed in Fig. 12. Fig. 12. LOM moulds converted in plaster using silicone negatives, and the final porcelain product obtained after casting a slurry in the plaster moulds. Fig. 10. LOM match plates of a soup plate (design Anabela Alves). c) To make a porcelain terrine, a two steps methodology was employed. In the first part, a CAD 3D file was materialized using the LOM process. After visual analysis, the terrine was divided in the 3 main components; cover, base and body. The moulds were also produced with the LOM process. After a quick finishing (without epoxy infiltration) a series of 3.2 Glass Industry. Rapid plaster, ceramic or metallic tooling can be obtained for the glass or crystal prototype manufacture or even glass limited mass production in a faster way than the traditional methods, if CAD 3D is used for design and engineering. Even spending more money, comparatively to the traditional processes, these new methodologies can

5 drastically increase the companies aggressiveness through the enlargement of the number of possible products to develop per time unit. 4. CONCLUSIONS Product development is the only way to increase competitiveness and maintain perspectives of future in ceramic and glass, independently of subcontracting demands. Nowadays, CAD 3D tools for artist design and tool design are imperative in every industrial product development department. It is possible to use the new generation tools of CAD 3D, RP and RT without collision with the objectives of keeping occupied the highly experienced and skilled technicians, because their functions are very important in the chain production and cannot be avoided in these methodologies. Using these new technologies and methodologies, companies can drastically increase the development capacity of new products, which are fundamental to increase the aggressiveness and competitiveness in a continuously more demanding market. REFERENCES Estratégia Educativa do Design do Produto. In: User Design, Congresso Internacional, FIL, Lisboa, March. Pham, D. and S. Dimov (2001). Rapid Manufacturing, the Technologies and Applications of Rapid Prototyping and Tooling, Springer V., London Ltd. Silva, P. Jorge, A. Barbedo Magalhães, Rui J. Neto and F. Jorge Lino (2002). Indirect Rapid Tooling Using Ceramic Moulding and Investment Casting Processes. In: RPD Rapid Product Development Advanced Solutions and Development, Semana de Moldes 2002, Centimfe, Marinha Grande, Portugal, 7-11 October. Vasconcelos, P., F. Lino and R. Neto (2001). O Fabrico Rápido de Ferramentas em Engenharia Concorrente. Tecnometal, Nº 136, pp Vasconcelos, M., P. Vasconcelos, F. Lino and R. Neto (2003). As Sinergias da Prototipagem Rápida e da Internet para um Design Optimizado. In: User Design, Congresso Internacional, FIL, Lisboa, March. Wohlers, T. T. (1999). Rapid Prototyping & Tooling State of the Industry, 1999 Worldwide Progress Report, Wohlers Associates, USA. Duarte, T., F. Lino, A. Barbedo and J. Ferreira (2002). Metallic Tools Obtained from Ceramic Moulding Using a Sol-Gel Process. CIMTEC 2002, 10 th Int. Conf. On Modern Materials & Techn., Firenze, Italy, July. Lino, F., F. Braga, M. Simão, R. Neto and T. Duarte (2001a) Protoclick Prototipagem Rápida, Protoclick, Porto, Portugal. Lino, F., H. Gamboa, B. Paiva and R. Neto (2001b). Direct Conversion of Rapid Prototyping Models. In: MATERIAIS 2001, 1 st International Materials Symposium, Faculdade de Ciências e Tecnologia, Coimbra, Portugal, 9-11 April. Lino, F., R. Neto, R. Paiva and A. Moreira (2003a). Rapid Prototyping and Rapid Tooling in Product Development of Ceramic Components. In: II International Materials Symposium, Materiais 2003 of Sociedade Portuguesa de Materiais, A Materials Science Forum, Faculdade de Ciências e Tecnologia, Campus da Caparica, Portugal April. Lino, F., R. Neto, R. Paiva and A. Alves (2003b). Potential of Rapid Prototyping and Rapid Tooling in the Glasss Industry, In: II International Materials Symposium, Materiais 2003 of Sociedade Portuguesa de Materiais, A Materials Science Forum, Faculdade de Ciências e Tecnologia, Campus da Caparica, Portugal, April. Neto, R., and F. Lino (2002). A Prototipagem Rápida na Indústria Nacional. Tecnometal, Nº 143, pp Pereira, A., E. Silva, M. Vasconcelos, P. Vasconcelos and F. Lino (2003). Design, Indústria e Tecnologia de Ponta. Um Caso de Estudo na

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