• Journal of the Korean Society for Precision Engineering
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• v.23 no.11 s.188
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• pp.7-16
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• 2006

• Journal of the Korean Society for Precision Engineering
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• v.22 no.10 s.175
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• pp.99-106
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• 2005

This paper presents manufacture of mock-up by HSM and optimization of machining condition for high productivity in the view of manufacturing time and accuracy. The rapid machining of prototypes plays an important role in building mock-up. Rapid Prototyping(RP) is a technology to make prototype. But, it have many problems such as shrinkage. deformation and formation occurred by hardening of resin and stair shaping. On the contrary, high speed machining(HSM) technology has many advantages such as good quality, low cost and rapid machining time. HSM and RP is compared for machining efficiency. Experiments are designed by Latin Square Method and machining condition is optimized and selected by ANOVA. For example, propeller is machined by the surface machining of thin surface parts.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.196-203
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• 2004

SL(Stereolithography) part is made by piling up thin layers which causes the stair stepping effect at the surface of SL parts. The effect brings about excessive surface roughness and cuts down the merits of using SL part. Hence, additional post-machining finishing such as traditional grinding is required. But the traditional post-machining is detrimental to part geometry and time consuming. In this study, therefore, a paraffin coating and grinding post-machining is newly proposed to improve the surface quality of SL fart. The paraffin which has suitable properties for the proposed post-machining is coated all over the part surface. By grinding the only over-coated paraffin based on boundary of the SL part surface, the surface roughness can be improved without any damage on the part. Also, it is verified that SL part finished by the proposed post-machining process can be applied for rapid tooling as pattern through manufacturing silicon rubber molding and casting test.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.158-163
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• 2001

This study is the selection of optimum forming condition for RP system using ADS. Program using ADS reduces the required time for feedback between design and manufacturing of workpiece. When we produce rapid prototype using RP system, we investigate the relationship between Facetres in system variable number of AutoCAD and roundness of rapid prototype, and we will find optimum forming condition in RP system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.204-209
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• 1995

The implementation of rapid prototyping technologies has been developed for automotive engineering by utilizing concurrent engineering principes integrated with slective laser sintering. The Selective Laser Sintering, in which a part is generated in layers form powder using a computer-controlled laser scanning apparatus and power feed system. An over view of the basic principles of SLS Machine operation is given. Binding mechanisms are described for power which becomes thermally activated bye the scanning laser beam; viscous flow and melting of a low-melting-point phase in powder. The production of parts from metal is described, including post processing to improve structural integrity and induce a transformation.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.62-67
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• 1999

The RP&M(Rapid Prototyping and Manufacturing) is the most appropriate technology for the small-lot production system, in which the production cycle is getting shorter owing to various needs from consumers. Recently RP products which are made of plastics, wax, and paper are used to verify the design of samples. But these products cannot be applied to the real mold because the strength enough to be a mold cannot be given by soft materials such as plastics. So RP products are copied to AFR(Al powder Filled Resin) molds or metal molds, which is called the RP&M. In this paper, RP&M is applied to a casting process. A porous casting mold, which is made from ceramic powder and binder, is used for rapid tooling of aluminum shoes molds.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.2
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• pp.104-110
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• 2016

The process of three-dimensional (3D) printing (also known as "rapid prototyping" and "additive manufacturing") uses computer-created digital models to produce 3D objects with a desired shape by stacking materials through a layer-by-layer process. The industrial potential and feasibility of 3D printing technology were recently highlighted in President Obama's State of the Union address in 2013. Since his speech, worldwide investment in and attention toward 3D printing technology have increased explosively. In addition, a number of 3D printing technology-based start-up companies have been established and evaluated as emerging enterprises making successful business models. In this paper, successful start-up companies (domestic and overseas) based on 3D printing technology will be reviewed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.50-53
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• 2003

Most companies use technologies such as stereolithography, selective laser sintering, and fused deposition modeling to make parts for such small consumer products as telephones, heads, and shoes. The largest part that the existing RP systems can make is only 600 mm in length. Because most RP systems build parts by depositing, solidifying, or sintering material point-by-point, making larger objects takes a long time. and in many cases, large objects won't fit the build size. A new effective thick-layered RP process. Transfer type Variable Lamination Manufacturing using expandable polystyrene foam (VLM-ST) has been developed with thick layers and sloped surfaces. In this paper, a scaledown model of F16 Fighter with the length of 800 mm is rapidly fabricated using the VLM-ST process. In order to build a CAD model of F16 larger than 600 mm in length, the approach in VLM-ST is to build larger parts in multiple sub-parts and then glue them together. The fabricated result shows that the VLM-ST process employing thick layers and sloped surfaces is adequate for creating the real-sized large objects in the diverse fields such as automobiles, electric home appliances, electronics. and etc.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.101-108
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• 2017

Recently, the patent rights for 3D printing technology have expired, while 3D printers with RP (Rapid Prototyping or Additive Manufacturing) and 3D printing technologies are receiving attention. In particular, the development of 3D printers is rapid in Korea, thanks to the increasing sales and popularity of FDM (Fused Deposition Modeling or Fused Filament Fabrication) 3D printers. However, the quality and productivity of the FDM 3D Printer are not good, so customers prefer the DLP (Digital Light Processing) method to avoid these shortcomings. The DLP method has high quality and productivity. However, because of the stereolithography equipment, it has few studies compared to optimal values for elements then FDM 3D printing study. In this study, to find the optimal conditions for 3D printing with the DLP method, the aim is to obtain the optimal values (strength, final time, quality) by changing the light exposure time, layer thickness, and z-axis speed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.63-68
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• 2015

Recently, 3D printer technologies have been used in many research efforts for high precision manufacturing. In particular, the rapid prototyping technology has been developing rapidly, because it can be manufactured in a short time with a 3D designed shape. This paper relates to the production characteristics of the straight bevel gear designed using a 3D print using the PolyJet method. The characteristics of a 3D printed straight bevel gear were compared with a machined straight bevel gear. The accuracy of the produced straight bevel gear was evaluated by backlash, meshing pattern, face angle, root angle, and surface roughness.