Printable Cone Chart: A Handy Reference for Pottery and Ceramics
For anyone working with ceramics, understanding kiln temperatures is essential to achieving consistent, high-quality results. One of the most reliable tools used in pottery studios around the world is the pyrometric cone chart. Having a printable cone chart on hand can simplify the process of monitoring your kiln and ensure your pieces fire correctly every time.
What Are Pyrometric Cones?
Pyrometric cones are small, pyramid-shaped devices made from ceramic materials that are designed to bend at specific temperatures inside a kiln. They have been used for over a century, with companies like Orton being among the most well-known manufacturers. Unlike digital thermometers or thermocouples, pyrometric cones measure heat work — a combination of both temperature and time — rather than temperature alone. This makes them an invaluable tool for potters who want to ensure their clay and glazes mature properly.
As the kiln heats up, each cone is designed to soften and bend at a precise point. When potters open the kiln after firing, they check the position of the cones to determine whether the kiln reached the correct temperature for the materials inside.
Why Use a Printable Cone Chart?
A printable cone chart serves as a quick visual and written reference that translates cone numbers into approximate temperature readings. Since cone numbers do not directly correspond to a single temperature value, having a chart nearby helps potters decode what each cone's bending position means.
Here are some key benefits of keeping a printable cone chart in your studio:
- Quick reference during firing: Instead of memorizing cone-to-temperature conversions, you can glance at your chart at any time.
- Helps with kiln programming: If you are setting up an electronic kiln controller, knowing the approximate temperatures for each cone number makes programming much easier.
- Useful for beginners: New potters often find cone numbers confusing. A clear, printable chart bridges the gap between cone designations and the Fahrenheit or Celsius readings they are more familiar with.
- Studio organization: Posting the chart near your kiln creates a culture of accuracy and consistency in your workspace.
Understanding the Cone Chart Numbers
Pyrometric cones are typically categorized into three ranges:
- Orton Self-Supporting Cones: These are the most commonly used cones in modern studios. They stand upright on their own and are placed in a cone pack that is visible through a kiln peephole.
- Large Cones: These older-style cones require a base and are less common in contemporary pottery but are still referenced in many cone charts.
- Small Cones: Often used in industrial applications, these cones are smaller and less frequently encountered in hobby or studio pottery.
Cone numbers range from very low (such as cone 010) to very high (such as cone 12). The numbering system can be confusing at first. Cones numbered with a zero and a dash (like cone 06) represent lower temperatures, while cones numbered without a zero (like cone 6) represent higher temperatures. In general, as the cone number increases without a zero prefix, the firing temperature also increases.
For example, cone 06 fires at approximately 1,830°F (999°C), while
