設計・制御
Four Zones
Japanese: 4ゾーン
A design framework that views the firing process in terms of four stages: “no cracking, no warping, no staining, and beauty.” Based on Rei Narioka’s books (2012/2021).
Learn More
The 4-Zone method designs glass fusing firing programs with the following four-stage objectives: “① Prevent cracking (by managing temperature rise, quartz transition, and rapid cooling),” “② Prevent warping (by managing slow cooling and cooling rates to prevent residual stress),” “③ Prevent Staining (Prevent opacity loss and discoloration: manage passage through the nucleation zone and maintain furnace cleanliness),” and “④ Achieve Beauty (Realize the intended expression: controlled by peak temperature, hold time, and cooling).”
Using the 4-zone concept makes it clear which purpose each step of the firing program serves, and it also makes it easier to identify the cause of problems when they occur. By understanding “why this step exists” in relation to the zones, you develop design skills based on principles rather than simply memorizing numbers.
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.