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Garden Sculpture in the Works Part 1

Garden totem in the works!  Quite a few years ago shortly after I met Steve Fabrico I went to his studio and took a weekend workshop with him on his handbuilding technique.

I’ve done a couple of these sculptures with the techniques he taught and am pleased I’ve got time to do this type of work again.

 

The pieces are super soft at this stage and since they are quite thick I’ve put them back in their molds (except the roundish one) so the pieces would keep their shape until dry. I had to shorten the tall mold or it would not have fit into my kiln. I’ve made a top and a bottom of each piece and put them together.

My next issue, how am I going to get the base piece into the kiln without damaging it? I think I’ve got that figured out too. Wrap in paper, put back into mold, put it on a small kiln shelf that I can leave underneath the piece while it’s being fired.

Most of the pottery I do is low fire earthenware but if a piece is going to be out in the weather it needs to be stoneware. What’s the difference?

From “The Basics of Pottery Clay” by Beth Peterson….

What is clay? Is it simply dirt? Well, yes and no. “Dirt” covers a lot of ground, so to speak. We can break dirt into several sections: topsoil, clay, inelastic earth, and rock. Topsoil contains a lot of organic material, which makes it good for growing plants. Clays and inelastic earths are the results of decomposing rocks, in which the particle size is extremely small. Rocks include bedrock and boulders all the way down to fine sand. Most clays contain several different types of clay minerals with different amounts of metal oxides and organic matter, this is what sets the different types apart. 

Clay differs from the inelastic earths and fine sand because of its ability, when wet with the proper amount of water, to form a cohesive mass and to retain its shape when molded. This quality is known as clay’s plasticity. When heated to high temperatures, clay also partially melts, resulting in the tight, hard rock-like substance 

Classes of Clay

There are many different types of clay bodies you can work with.  Clay can be divided into several classes, based on characteristics and at what temperature the clay must be fired to in order for it to become mature, or reach its optimum hardness and durability.

The three most commonly used clay bodies are earthenware clay bodies, mid-fire stoneware clay bodies, and high-fire stoneware clay bodies. 

Earthenware Clays

Earthenware is the most commonly found type of found clay. Earthenware clays were some of the earliest clays used by potters, and it is the most common type of clay found. These clays are highly plastic (easily worked) and can be sticky. Earthenware clays contain iron and other mineral impurities which cause the clay to reach its optimum hardness at between 1745°F and 2012°F (950°C and 1100°C).   – Unless totally covered with glaze it will remain somewhat porous.

Stoneware is fired at very high temepratures. 

Stoneware clays are plastic and are often grey when moist. Their fired colors range through light grey and buff, to medium grey and brown. Fired colors are greatly affected by the type of firing.

Mid-Fire Stoneware Clay Bodies are formulated to fire to maturity between 2150°F and 2260°F (1160°C and 1225°C).

High-Fire Stoneware Clay Bodies   fire to their mature hardness between 2200°F and 2336°F (1200°C and 1300°C).

When fired to maturity some of the clay particles melt and the clay turns to stone, making it impervious to water.

I hope I’ll have time over the next year to do a lot of sculpture!

Phase two – bisque fire the individual pieces.

Next post – figuring out my glazes and sculpting the top.

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