SSB8
Cone 8 · Bends 1211°C (2212°F) at 15°C/hr (slow) · Bends 1249°C (2280°F) at 60°C/hr (medium) · Bends 1271°C (2320°F) at 150°C/hr (fast) · 63.5 mm (2½ in) tall, ceramic · Built-in base — no cone plaque, clay pat, or wire holder needed · Mounting height and 8° angle preset at the factory · Endpoint is a 90° bend, tip level with the base · Contains crystalline silica — do not grind or breathe the dust
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Bends at 1249°C (2280°F) at 60°C/hr, with slow and fast rates published as well. The base is moulded in, so it needs no plaque or holder. For porcelain, stoneware, china and floor tile.
Cone 8 in Orton's self-supporting (SSB) series. It bends at 1211°C (2212°F) at 15°C/hr, 1249°C (2280°F) at 60°C/hr, and 1271°C (2320°F) at 150°C/hr, each measured over the firing's last 100°C. The patented base is moulded in, so it stands on the kiln shelf straight from the box, with no plaque or wire holder and no mounting angle to set. Those figures are not a tolerance: a cone measures heat-work, time and temperature combined, so the firing rate decides which number applies. Needing no mounting, it is the usual choice for witness cones and test firings, read at a 90° bend with the tip level with the base.
