Most of us don’t think of the pottery wheel when we think about making slab built pottery. But there’s no reason to overlook this piece of equipment when slab building. The pottery wheel can yield some pretty cool results as you can see in the image to the left.
In today’s post, an excerpt from his book From a Slab of Clay, Daryl Baird explains how you can use the wheel to make a slab with a spiral texture, which is quite challenging with any other method. – Jennifer Poellot Harnetty, editor.
The pottery wheel presents two ways to make slabs‚ horizontally and vertically (which is covered in From a Slab of Clay). The horizontal approach might be the least-used, but wheel-thrown slabs have some unique properties and there are those who actually prefer them.
A comparatively thick slab of clay is spread out on the wheel head then allowed to firm slightly. After drawing a cutting wire across the bottom on the slab, it’s lifted from the wheelhead and laid on the work surface. As expected, lifting and transporting the clay to the work surface deforms the circular slab; but this can be minimized by first underscoring the periphery of the slab with a trimming tool then rolling it up and onto a rolling pin or sturdy cardboard tube.
Working with slabs
In From a Slab of Clay you’ll discover everything you need to know about working with slabs. From setting up a proper working space to selecting the right tools and equipment—including complete instructions for building your own slab roller—Daryl doesn’t miss any details. Includes 16 slab project demonstrations and a gallery of selected works from ceramic artists.
Optionally, the wheel-thrown slab can be allowed to firm up on the wheel head after cutting. This firmer slab loses some of its workability but it can be lifted and transported with less deformity. Clay slabs thrown on plastic or wood-composite bats can be removed from the wheel head and placed next to the work surface before removal. Bats made from plaster can be especially useful since plaster wicks moisture from the underside of the slab while it’s going through controlled drying on the top surface. As the clay firms up and starts to shrink, it releases from the plaster bat with little or no effort.
It’s important to develop a technique where you can apply even compression of the clay across the surface, from center to edge. Doing so makes for a stronger slab that’s more likely to keep its shape. What makes wheel thrown slabs distinctive are the concentric and spiral textures that can be added to them. Running a finger across the clay as the wheel spins can make a simple, spiral ridge. More detailed textures can be applied using roulettes, stamps or any combination of them. Once the slab is decorated and released from its bat, it can be cut into shapes or wrapped around a form.
**First published in 2013.