Temperature and humidity effect the drying rate of clay. Dry, warm and windy weather cause clay to lose moisture rapidly. Small pieces are easier to dry than large and thick walled ones. Keep the clay moisture content balanced between all the various thicknesses of the piece to achieve complete drying without cracking. Since clay shrinks as it dries, controlling a humid environment around the clay equalises the moisture and slows drying. Cracks form when various sections of a clay item dry at different rates.
Cover the parts of the clay item you are not immediately working on with cling film to keep them moist.
Set the clay item out of the wind and sun while drying.
Drape wet cloths or cling film over the entire piece to keep the air around the clay humid. Do this while taking breaks as your piece progresses.
Turn your clay products frequently while drying to reduce the chance of cracking or warping. Bowls and plates may be stacked rim to rim.
Wrap any added parts in damp towels. Dry pots with handles upside down so the rim dries slowly and the handle stays secure.
Place paper under clay items to prevent them from sticking to the table surface and causing uneven drying.
Spray the inside of a plastic bag and place it loosely over your clay creation. The clay can indirectly absorb moisture from this technique.
Dry clay for two to three weeks to be certain all the moisture is removed before firing. Dry clay feels cool when touched.
Add course grog or sand to thick walled items so they dry slower.
Make sure one area does not get extremely saturated with water while another starts to dry. This will cause cracking.
Tips and warnings
- Add course grog or sand to thick walled items so they dry slower.
- Make sure one area does not get extremely saturated with water while another starts to dry. This will cause cracking.