A bat is a flat, removable disc that attaches to the wheel head so you can throw on it and lift the finished piece off without touching the soft clay. Bats are usually made of plastic, MDF, plywood or plaster.
What Is Bat?
Most wheel heads have two holes for bat pins, metal pins that locate the bat and stop it slipping while you throw. You can also stick a bat down with a thin pad of clay. Once the piece is thrown, you wire under it and lift the whole bat away, which keeps wide or delicate forms from distorting.
Bats are almost essential for plates, platters and wide bowls, which are hard to lift by hand without warping. They also free up the wheel, so you can throw several pieces in a session and leave them to firm up on their bats.
Plaster bats draw water out of the clay, which helps pieces release and dry evenly, but they chip and must be kept away from reclaim clay because plaster fragments in clay can blow out in the kiln. Plastic and wooden bats are the usual choice in teaching studios because they are tough and easy to clean.
This pottery glossary entry from Le Studio Art Space is general educational content. Always follow the clay, glaze and kiln makers’ data for your own materials and equipment.