Large cones must be mounted in a plaque with the cones mounted at 8 angular degrees. Plaques can be made by hand or purchased through Orton. Orton stocks both 3 hole and 4 hole plaques.

Place standard large cones in a holder or cone plaque designed to hold them at the proper 8-degree angle. If using self-support cones, their special built-in base will place them at the correct angle. Place cones in order: Guide\Fire\Guard. (For example, to fire to cone 05, place the cones facing left 06\05\04). This allows each cone to melt without interfering with the others. Cone plaques should be visible through your kiln’s spy holes during firing so that you can monitor your progress and manually shut down if automatic devices should fail. Additional cone plaques can be placed in other areas of the kiln for analysis after firing is completed. They will tell you if your kiln fires evenly throughout or where your hot and cold spots are.

CONE NUMBERS - Orton makes cones from cone 022 up to cone 42. Cone 022 is the lowest melting cone and requires the least amount of heat to deform or bend. During firing, a cone softens and melts as it is heated. Cones used on the kiln shelf bend due to the effects of gravity pulling the tip down. This bending indicates the cone and the ware have received a specific amount of heat. It typically takes 15 to 22 minutes for cones to bend fully once they start bending. Each higher cone number requires more heat to bend. A cone 01 needs less heat treatment than cone 1 and cone 020 needs less than 019.

• Low-Fire (cone 06-04)
• Mid-Fire (cone 5-6)
• High-Fire (cone 10+)

1 Box contains 50 Large cones

Orton Resources: https://www.ortonceramic.com/pyrometric-cones