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Large (Standard) Cones
Large Orton Pyrometric Cones remain an essential part of the firing process for potters, educators, and ceramic manufacturers. These pyramid-shaped ceramic devices measure heat work precisely, allowing potters to monitor whether their work has received the correct amount of heat during kiln firing. Standard Orton cones are made from carefully controlled compositions, ensuring repeatable results across a minimal temperature range. Browse a selection of Large Orton Cones at Potclays below.
Why Use Large Orton Cones?
Large Pyrometric Cones provide a practical method for monitoring the heatwork within a kiln. Quality-conscious manufacturers use them to assess heatwork across different sections of their kiln visually. While pyrometers or controllers measure temperature hourly, Orton cones account for the combined effects of time and temperature, offering a far more accurate reading of the firing process.
Pyrometric cones measure heat-work rather than temperature alone, enabling potters to ensure their work receives the correct amount of heat regardless of firing rate, load density, or airflow. Large cones must be mounted on a plaque, with the cones positioned at an angle of 8 degrees.
Click here to download our Orton Cones Conversion Chart
Differences Between Cones
Orton offers a wide range of cones, each formulated to bend at a specific temperature range. Cones prefixed with a zero indicate low-temperature firings, while cones without a zero suggest higher temperatures, typical of stoneware and porcelain.
Witness cones, often set in groups of three – one below, one at the target, and one above – are crucial during the firing process. They monitor the kiln’s progression and ensure an even distribution of heat. Slender pyramids, which bend in a controlled and repeatable manner, remain one of the most trusted devices for potters seeking accuracy beyond what a thermocouple or automated shut-off can provide.
Why Choose Potclays?
At Potclays, we have over 90 years of experience in the ceramics industry and use this to provide the very best in clay, glazes, machinery and tools and accessories. We're proud to be a one-stop shop for potters of all skill levels, providing products for hobbyists, educators and professionals.
Need help finding the right pottery supplies for your projects? Get in touch with us today.
