The slab pot technique is a method of handbuilding pottery using slabs of clay. It involves rolling out sheets or “slabs” of clay and using them to construct functional pots and vessels. The slab pot technique allows for a high level of control over the final form, as slabs can be cut into shapes and joined together. It also minimizes the amount of wheel throwing skill required. Let’s take a closer look at how slab pots are made.
Making the Clay Slabs
The first step in slab pottery is preparing the clay slabs. This involves taking a lump of clay and using a rolling pin or slab roller to roll it into a flat sheet. The slab should be rolled out to an even thickness, usually 1/4 inch or thinner. The slabs can be any shape, but rectangular slabs are most common. A slab roller tool specially designed for making clay slabs allows for faster rolling of uniform slabs.
Cutting and Forming the Pieces
Once the slabs are rolled out, they can be cut into pieces using fettling knives, pottery wires, or cookie cutters. The shapes and sizes of the cut pieces will depend on the desired final form. For example, long rectangular strips might be cut to form the sides of a cylinder, while a round or oval base can be cut for the bottom. The sides should be cut approximately the same height as the final piece will be tall. Decorative elements like fluting or texturing can be added to the slabs before assembling them.
Joining the Slab Pieces
The cut slabs must then be joined together to form the pot. This is done by applying “slip,” which is watered down clay, between the slab edges as glue. The pieces can be joined using a few techniques:
- Score and slip – Scoring or scratching the clay surface and applying slip to “glue” joints
- Overlap seams – Overlapping slab edges slightly and blending them together
- Coil joins – Adding thin coils of clay between slab seams
The joints should be smoothed together firmly from both sides to bond the pieces. The pot’s form starts becoming visible as the sides are joined to the base piece.
Refinement and Drying
Once constructed, the basic pot form can be refined. The edges can be trimmed and neatened using metal loop tools. The surface can be burnished or textured. Sprigs, handles, feet, and other elements can be added. The pot should be allowed to dry slowly and evenly to prevent cracks and warping. Drying times depend on factors like thickness but usually range from several days to weeks.
Firing
When bone dry, the pottery piece can be fired in a kiln. Firing hardens the clay permanently through sintering. The clay undergoes both physical and chemical changes during the firing process. Typical firing temperatures for stoneware clays are around 2,200°F to 2,400°F. Multiple firings at progressively higher temperatures are often used. The pottery can be left plain after firing or decorated with glazes and fired again.
Advantages of Slab Construction
Some of the benefits of handbuilding pottery using the slab technique include:
- Versatility – Many shapes and forms can be achieved.
- Control – The piece can be meticulously planned and formed.
- Ease – Does not require extensive wheel throwing skills.
- Texture – It’s easy to impart pattern and texture.
- Strength – Slab pots can have thick, sturdy walls.
- Large scale – Good for making big pieces.
Tips for Successful Slab Building
Follow these tips for best results when making slab-built pottery:
- Use the right clay – Stoneware or porcelain clays are best.
- Make uniform slabs – Roll them to an even thickness.
- Blend seams thoroughly – Eliminate weak points.
- Support forms – Use foam or other fillers while drying.
- Dry evenly and slowly – Prevent cracks and warps.
- Fire properly – Do multiple firings if needed.
Common Slab-Built Forms
Many types of pottery vessels can be made with the slab technique. Some of the most common include:
- Boxes – All sides made from slabs.
- Bowls – Slabs for sides, slab or thrown base.
- Platters – Slab base and short sides.
- Tiles – Decorative slabs for wall hanging.
- Vases – Vertical slab sides and base.
- Figurines – Hollow slabs sculpted into shapes.
Conclusion
Working with slabs opens up creative possibilities beyond wheel throwing. Mastering the slab pot technique provides potters with an versatile handbuilding method for realizing their ideas in clay. With practice, both functional pots and decorative works can be produced using this approach. Slab construction is an important skill for any aspiring ceramic artist to learn.