Some time back I posted about getting back into my clay studio. I had been M.I.A. for a few years due to a flagging economy, health concerns, and lack of any creative impulse.
Using the wheel to throw pots was getting increasingly hard on my back so I decided to experiment with “hand building”, a potter’s term for making things with clay without the wheel or the use of plaster molds.
I needed to make replacements for some tiles that broke in a display in the lobby of a hospital that bought some wall murals from the studio and gallery I used to work in. These replacements were my first efforts after I got back in. Several of them warped. I have possible technical explanations for that. One of them is that the process used “slab inlay” where one colored clay is pressed into another color of clay. Two things happen; clay is displaced so that the borders of the piece have to be reshaped. This manipulation can cause clay to develop a memory for a shape you did not intend.
The second issue is that the clay “bodies” need to be very similar. They need to have the same shrinkage rate during drying and firing. If they are very different they can actually pull apart, but more often they just pull at each other and change shape.
I noticed that the dark clay body warped worse than the white clay. I’m not sure why that happened.
The second set of tiles is representative of a series of “Eclipse” tiles that I made for the coming solar eclipse. Dillard, Georgia about 12 miles up the road is on the path of “totality”. Every motel room has been sold out for over a year. We are expecting a busy weekend and rural gridlock.
These tiles were created using a slab roller instead of a rolling pin. They are more consistent in thickness, thinner, and created from the white clay for the ones that have the arbor vitae imprint, and from dark clay for the other set. Again, some of the dark clay tiles warped, and did so without slab inlay.
These tiles were the product of desperation and utilized several untested techniques, colorants, and a glaze that I had modified and had not yet tested. Except for losing a couple of the dark clay tiles to warping they worked out. The colorants were diluted clay slip that I sprayed on creating thick and thin areas of light in the background, the dark side of the moon was created using a black mason stain and a material called Gerstley Borate. The streaks away from the sun were supposed to be yellow. I mixed a yellow mason stain 50/50 with the Gerstley which made them too dark, but then serendipity helped me out.
The glaze is based on a barium glaze that a potter named Rene Murray was kind enough to share. Barium is a potential problem. It aids in modifying and enhancing colors in glazes, but it is not food safe. So, I went to the books and modified the glaze substituting another material high in calcium for the barium on a mole for mole basis (pm me if you want any information about this).
Rene’s barium glaze was turquoise blue-green. I used the same colorants and it is a pretty green without the blue. I used the same percentages of colorants that she did, but the color is more intense and it provided a wonderful amplification of texture. And that effect served to highlight the streaks that were supposed to be jets of gasses from the sun’s corona that turned out too dark, providing a halo around those streaks. I would like to tell you that I planned that, but it was luck.
I usually run a set of test tiles in a glaze firing. This time I found three out of eleven that I liked, and two used the glaze I modified.
It is interesting that the modified glaze seems to be temperamental about the way that it is applied. All of the work was dipped once for about a second except a large piece over which I poured the glaze letting it run off the edges, and a set of flat test tiles that had the glaze brushed on. The brushed on glaze was blue over both light and dark clay. The large piece was green, but its thickness almost obscured the underlying clay.
Test tiles help avoid kiln disasters. Some glaze combinations melt and run like crazy and can create a real mess on your kiln shelf. One of my test tiles did that, but the run stopped just short of contact.
Runny glazes can create cool effects when you are expecting the glaze to move. They look good on the rims of mugs, and some potters create “dams” on the side of pots by creating a lot of texture and then apply the runny glaze above the dam creating thick and thin areas which produce interest.
for some reason I can no longer add images to this post from my computer. Perhaps, I can find a workaround.