overdrying and underdrying

Due to a delay in the firming response of the clay, accelerated drying can easily be overdone or underdone. It varies with the mass of clay needing to be heated and compounded by the time it takes for moisture to travel through the wall to reach the surface and evaporate. Patience and active monitoring of the temperature and dryness of the clay is advised. Strive for fresh clay at the rim and a firmness of roughly early leather hard beneath the rim. The temperature of the clay should never be so great it cannot be touched.

The whole clay wall continues to dry throughout the process. Spray the surface with water if you feel the wall is becoming too dry and hard.