Working with Clay: Rolling out the Slabs!

I especially like working with slabs. This is a horse that has not been fired yet. I constructed it with slabs and painted it with colored slip. I am only low firing it with a clear low fire glaze over the colored slip. I want to see the difference in high fire and low fire on my slip colors.

Building a Ceramic piece out of slabs has its challenges but is also very versatile. Slabs can be shaped and impressed with texture and designs.

To start a slab piece you may want to make a pattern. Patterns can be made out of paper, poster board or cardboard. First tape your pattern pieces together to see if they are the right size and fit together before you use them. You can adjust the size but:

Take my Advice:  Ceramics, especially high fire stoneware shrinks in the drying and firing stages up to 20%. Make your piece is larger than you want the finished piece to be.

Make sure you prepare your clay before you start. When rolling out a slab of clay you are compressing the clay more and you may see air bubbles. Make sure to pop them with a pin tool and roll them out again.

 

Your slabs need to be hard enough to hold their shape before you put a piece together You may want them to also be soft enough to shape into a cylinder like my second example.  When first starting do not leave your slabs uncovered unless you can check on them every 30-45 minutes.

Take my Advice: To make sure your seams are secure put slabs together when they are as soft as you can.

There are two ways I put slabs together. For some pieces I miter the seams by cutting them at an angle with my pin tool (or one of my Dental tools).

 

Before you put edges together put some slip (watered down clay) on the edges and have a small coil ready to help secure the seam.

 

Push coils into the seams and then smooth them out – both on the outside and inside of your seams.

Use tools to smooth and even out the sides and seams.

You can then add feet to your piece. Here are some examples of feet.

Another way to attach slabs is with a straight edge. You also want to score the edges and add slip and coils to help them be secure.

 

For my cylinder mug I am not going to add feet. When you have a flat bottom you want to make sure you do not add glaze very close to the bottom or it will attach to your kiln shelves.

Here are some of my Slab Constructed Ceramic pieces.

I carved the surfaces with relief sculpture and I also used colored slip, stain and glaze.