Air bubbles are expelled from clay through the _____ process

Kneading clay forces out trapped air bubbles. Potters fold and press the clay repeatedly. This creates smooth, bubble-free clay.

Coiling builds forms from clay ropes. Firing hardens clay in kilns. Kneading is the preparation step that removes air.

Air bubbles cause problems during firing. They can crack or explode the pottery. Proper kneading prevents these defects.