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Ceramics techniques - EduqasSlip casting

Find out about the different ways to use and build clay and various finishing techniques that can be used to colour and decorate clay objects. These methods have advantages and disadvantages and require different skills, techniques and equipment.

Part of Art and DesignSculpture

Slip casting

slip cast object being removed from mould
Figure caption,
Slip casting uses a mould to create identical objects

Slip is a liquid mix of clay, water and sometimes other materials, such as pigment.

A mould is made by attaching a frame around an object and pouring plaster over it. A thin layer of grease, such as soft soap, has to be applied first to prevent any sticking.

When the mould is dry, the original object is removed. The mould then needs to be left until it is dry.

The mould is held together using strong, gripping bands. A pouring hole is created during the mould-making stage to allow the slip to be poured in.

A hand holding a blue jug and pouring liquid clay into holes in the tops of white boxes

Liquid clay is poured into the mould

The plaster mould will absorb much of the water from the slip, leaving a clay powder that coats the inside surface. When enough time has passed, the excess slip is tipped out.

A clay jug in a mould with its handle broken

The mould is opened to reveal a three-dimensional form. where the moulds attached together can be scraped away before the object is ready for firing.

A mould can be reused. This process is used to functional ware such as cups, vases and teapots as well as other decorative pieces.