設計・制御
Joint Design Rule
Japanese: 継ぎ目設計則
A design principle for composite layouts that requires the joints between the upper and lower glass layers to be offset. If the joints overlap, it can cause dents or delamination during firing.
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The Joint Design Rule is a design principle for composite layouts (configurations in which glass is cut and stacked in two or more layers) that requires the joints (the positions of the cut lines) between the upper and lower layers to be offset from one another. Rei Chikaoka (2021, p. 45) has explicitly defined this as a practical protocol. If the joints of the upper and lower layers coincide at the same point, this can cause the area to凹む (depress) during firing or lead to the separation of the glass at that point.
The design solution is simple: intentionally offset the joint position so that the center of the glass in the upper layer aligns with the position where the cut line from the lower layer will be. It is recommended to offset the seam by at least the width of the seam (the edge width after scoring and breaking). This design rule is important not only for avoiding stress concentration at the seam but also for ensuring flatness after firing. It is a principle that should be given special consideration when designing large-scale fused glass works with a stained-glass-style segmented composition.
Related Concepts
Understand the practical criteria for fusing design, including the plate-count effect, an 8-stage firing program, press fusing, and block fusing.
This entry is written in Japanese by Rei Chikaoka and translated for readers outside Japan. If something reads oddly, the original is the source of truth.