Ceramic Plaster Mold

Ceramic Plaster Mold is a specialized tool used by potters and hobbyists to create consistent ceramic shapes through a process called slip casting or press molding. Essentially, it acts as a negative "template" that dictates the final form of the clay.

1. Material & Composition

Unlike standard construction plaster, these molds are made from high-quality pottery plaster (such as No. 1 Pottery Plaster). This material is chosen for its specific porosity; it is designed to remain sturdy while remaining "breathable" enough to absorb water.

2. How it Works (Slip Casting)

The most common use for these molds is slip casting:

• Pouring: A liquid clay called slip is poured into the dry plaster mold
• Absorption: The porous plaster immediately begins to pull water out of the slip. As the water is absorbed, a layer of solid clay builds up against the interior walls of the mold.
• Draining: Once the desired thickness is reached, the remaining liquid slip is poured out.
• Release: As the clay dries further, it shrinks slightly and pulls away from the mold, allowing the "greenware" (unfired clay) to be removed.