Fv

F.A. van der Weijst

info

Please Note

2 records found

Conference paper (2020) - F.A. van der Weijst, F. Oikonomopoulou, M. Bilow
TCompared to flat sheets of float glass, cast glass components have a thicker geometry and thus a high buckling resistance. This buckling resistance in combination with the high compressive strength of glass make cast glass components suitable for the construction of fully transparent shell structures that are mainly subjected to compressive stresses. Shell structures often have the shape of surfaces with varying Gaussian curvature. When constructing such a shell structure out of cast glass components, components of varying geometries are needed. An adjustable mould was developed that can be used for the casting of glass components (i.e. voussoirs) of varying geometries. The possible voussoir geometries that can be cast in the adjustable mould are limited to voussoirs with planar, convex, polygonal intrados and extrados. These voussoirs can be used to construct fully transparent shell structures. The voussoirs are dry-assembled with a rubber interlayer in between. Tongue and groove shaped interfaces ensure an interlocking connection. By tessellating a shell structure, the shell structure is divided into a discrete number of voussoirs that can be cast in the adjustable mould. Several aspects have to be taken into account when optimizing the tessellation pattern including planarity, interior angle size, face size and alignment to the flow of forces. A design was made of a shell structure that covers the courtyard of the Armamentarium in Delft. This shell structure served as a case study used to demonstrate the tessellating process and the use of the mould developed during this research. ...

An Exploration on Novel Techniques for Generating Complex and Customized Geometries

This paper explores two alternative mould fabrication technologies that allow for the casting of (solid) glass components with a great degree of freedom in shape and size and/or of a customized design, in a cost-efficient way. In specific, the paper discusses the research, design and experimental work conducted at TU Delft on 3D-printed sand moulds and adjustable, high-precision steel moulds. 3D-printed sand moulds can provide a high-accuracy, cost-effective solution for solid glass components of complex geometry and/or of customized design. Although this mould technique is already used for metal castings, it remains still unexplored in the field of glass casting. Accordingly, this paper presents the first experimental findings at TU Delft of this mould technology: mould samples using different binders and treated with various coatings for surface finishing are tested in the high temperatures anticipated in glass (kiln-)casting. Following, 3D-printed moulds are prepared for a given glass geometry and physical glass prototypes are made by kiln-casting. Adjustable metal moulds are another mould technique that offers a degree of freedom in the modulus of a structure. Essentially, components of different sizes and, to an extent, shapes can be generated by the same mould. Accordingly, the design principles and engineering of such a mould and the potential applications and limitations of this technology are discussed. As a proof of concept, an adjustable mould is made using 3D-printed PLA and laser-cut MDF. The mould is used for the generation of wax models of variable forms, which are used to kiln-cast glass prototypes by the lost-wax technique. Based on the findings on both presented mould technologies, guidelines are given on their suitability according to the production volume, the level of accuracy required and the complexity and variation of forms involved. ...