• 한국산학기술학회논문지
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• 제3권2호
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• pp.136-140
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• 2002

정밀하고 복잡한 형상의 금속 부품을 제작하는데 사용되는 정밀주조법은 왁스형을 만드는 과정을 수작업으로 진행하므로 많은 시간과 비용이 소요되었다. 왁스형 제작공정을 개선하기 위해 쾌속조형기를 이용하는 방법을 제안하였다. SLS 형 쾌속조형기를 이용하여 캐스트폼형을 제작하고 여기에 용융된 왁스를 함침시켜 왁스형을 완성한다. 이 방법을 이용하여 스텐레스 스틸 소재의 금속 주분을 제작하였는데, 시간과 비용이 크게 절감되었으며 정밀도도 향상되었다.

• 대한치과기공학회지
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• 제26권1호
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• pp.105-114
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• 2004

This study obtained the following consequences, as a result of the comparative analysis for the castability depending on an angle of the sprue and wax pattern in case of manufacturing dental prostheses, for the castability depending on direction, and for the castablility of sprue, which attached the reserve to each different 3.5mm roll wax(sprue wax) and to 2.5mm sprue wax. 1. As a result of the comparative analysis for the castability depending on an angle of the sprue and wax pattern, the best castability was shown when the angle of the sprue and wax pattern is 180$^{\circ}\Delta$(straight line), and the lowest castability was shown in 45$^{\circ}\Delta$, which was curved most, and there was no statistical significance. 2. As a result of the comparative analysis for the castability of an angle depending on direction, the best castability was shown in the farthest side from the direction of centrifugal casting, and the lowest castability was shown in the same side as the direction of centrifugal casting, and there was no statistical significance. 3. Given comparing the castability depending on the pattern of sprue, the better castability was shown in 135$^{\circ}\Delta$ and 180$^{\circ}\Delta$ when using 3.5mm roll wax(sprue wax), compared to attaching the reserve to 2.5mm sprue wax.

• 대한치과기공학회지
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• 제30권1호
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• pp.9-15
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• 2008

An investigation was carried out to examine the pores of casting bodies depending on the position of wax pattern in the ring for precious alloy by optical micrographs. From the result of optical micrographs, many pores were found in the Group C that wax pattern is placed in the center of the ring. However, any pores were scarcely found in the Group A, B, D and E that wax patterns are placed out of the center of thermal zone. In comparison with the pores of casting bodies of Group C, many pores were found at the cusp area rather than at the proximal surface. From these examination, it was concluded that wax pattern should be placed out of the center of thermal zone to prevent casting boies from occurring pores.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.566-569
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• 2002

Rapid Prototyping is a prototyping technology that produces complicated parts directly form three dimensional CAD data with high efficiency, and has been extensively applied to various manufacturing processes. The aim of this research is to apply a 3D printer part as wax pattern in the investment casting process. The difference between conventional pattern wax and 3D printer wax is compared by experiments. The direct casting method is developed for ceramic-shell investment casting.

• 대한치과보철학회지
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• 제56권1호
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• pp.17-24
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• 2018

가철성 국소의치의 금속구조물을 제작하는 방법은 왁스 패턴을 제작하여 주조하는 lost wax technique이 주로 사용되어 왔으나, 디지털 기술의 발달로 서베잉과 금속구조물을 CAD (Computer aided design)로 디자인하여 제작할 수 있게 되었다. 여러 증례에서 CAD를 이용한 pattern의 프린팅 방식으로 얻은 레진 패턴이 구강 내에 정확하게 적합 되었고 최종 금속구조물 또한 좋은 적합도를 보였다고 보고되었다. 본 원저는 치조골 소실이 심한 상, 하악부분 무치악 환자에서 가철성 국소의치의 금속구조물을 두 가지 방식으로 각각 제작하였다. 첫 번째는 일반적인 lost wax technique과 두 번째는 CAD를 통해 pattern을 프린팅하여 금속구조물을 주조하는 방식으로 제작하여, CAD data와 fit checker를 이용해 금속구조물과 서베이드 크라운과의 유격을 측정함으로써 금속구조물의 적합도를 비교하였다. 두 가지 방식 모두 임상적으로 사용 가능한 금속구조물의 적합도를 얻었기에 이를 보고하고자 한다.

• 대한치과기공학회지
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• 제24권1호
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• pp.107-126
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• 2002

The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I am using compound method of wax bite technique and cone technique. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for mandible molar occlusion. The results of the study were as follows; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of mandible first premolar is appeared V form. 6. The development groove of mandible second premolar is appeared Y form. 7, The development groove of mandible first molar is appeared M form. 8. The development groove of mandible second molar is W form. 9. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 10. The buccal, lingual groove of molar is formed parallel with direction of teeth arrangement.

• 한국정밀공학회지
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• 제16권11호
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• pp.74-80
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• 1999

In this study, a stereolithography apparatus (SLA) prototype is used as a master model to be transformed into the silicone pattern by vacuum tool forming. The tool for the first prototype is fabricated by using this silicone pattern. Following this procedure, a temporary tool with metal powder and epoxy for wax injection is prepared for the die set of quick change type which consists of upper and lower base die나 and an insert die. The die set of quick change type appears to be very effective in casting operation by changing tools rapidly. The original wax pattern is formed through the die set, and is made of lost-was. Finally the lost-wax pattern is applied to investment casting. The final casting product is checked regarding its dimensional accuracy.

• 대한치과기공학회지
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• 제30권2호
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• pp.17-22
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• 2008

The purpose of this study was to observe the thermal expansion of the inlay waxes at temperature. Inlay pattern wax shows not only a high coefficient of expansion but also a tendency to warp or distort when allowed to stand unrestrained. The thermal expansion of inlay waxes was tested according to the treatment conditions for 10 minutes at $40^{\circ}C$ The thermal expansion of inlay waxes at various temperatures was measured with an electro dial gauge. The results were as fellows: 1. It is shown that the rate of thermal expansion of wax A is 0.2%, wax B is 0.29%, wax C is 0.38%, and wax D is 0.22% at $40^{\circ}C$ 2. It is shown that the coefficient of thermal expansion of wax A is $106{\times}10^{-6}/^{\circ}C$, wax B is $152{\times}10^{-6}/^{\circ}C$, wax C is $199{\times}10^{-6}/^{\circ}C$, and wax D is $116{\times}10^{-6}/^{\circ}C$ at $40^{\circ}C$ 3. The thermal expansion of the inlay waxes at $40^{\circ}C$ was shown to increase in the order of wax C, B, D, A.

• 한국정밀공학회지
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• 제24권6호
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• pp.131-137
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• 2007

In metal casting process, it is very difficult to predict the form accuracy of cast part and reduce repeatability error. In this study, the variations of form accuracy were measured in the process of metal cast prototyping, where RP part is manufactured from CAD model in the first, and then, wax part is cast in the vacuum environment using the RP part as master model, and finally metal prototype is cast using ceramic mold and the wax part as pattern. To investigate the variations of form accuracy, the averages and standard deviations of error distribution of the parts measured by 3D scanner were compared. It was observed that the biggest shrinkage is generated during the extraction of wax part in the second step and the biggest deterioration of form accuracy is generated during the metal part casting in the last step.

• 한국정밀공학회지
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• 제16권10호
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• pp.59-67
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• 1999

The lead time for new products is very limited in the current manufacturing processes, therefore the Rapid Prototyping process has been introduced and generally used in the industry. Fused Deposition Manufacturing (FDM) is one of the most common methods in this field. In the FDM process, the patterns are made of Wax of ABS and ABS shows better quality of the patterns. To date, the FDM/ABS patterns are used in investment casting for making silicon moulds to produce was patterns because it is very difficult to dewax FDM/ABS directly. The aim of this paper was to propose a feasibility of using FDM/ABS parts as wax-pattern substitutes in the investment casting process. The effects of casting conditions, such as pre-heat temperature and casting temperature, are provided. Comparisons with the conventional investment casting processes using the wax-patterns under the same prototype are made. Lead-time and saving cost are discussed in using FDM/ABS parts as was-pattern substitutes compared with the products from other rapid prototype systems.