More than Mud
By Tim Thornton, Tim Thornton Ceramics
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Ceramics is a great way to express creativity, but it needn’t just be shaping something by hand (or on the wheel) and then glazing it. Many schools already have the equipment to do much more than this, so pupils can get more out of the material. Here are some ideas to explore.
Fig. 1: Tony Hansen DigitalFire
3-d printing for a slipcasting mould. Bottom: CAD design for the outside half mug; Top right: Plaster cast of half mug from the 3-d print; Top left: Slipcast half mould taken from the plaster half mug
Where detailed, accurate or repeatable shapes are wanted, these are best slip cast by pouring liquid clay into a plaster mould. The mould soaks up the water, leaving leather hard clay. For freeform shapes such as pattern stamps, these can be carved into a plaster slab. But where a higher degree of accuracy is needed, or where the design may already exist in digital format, there are a couple of approaches to take. For flat pieces like tiles, or the decorative sprigs that are put onto the clay surface, a simple desktop 3-axis CNC machine can cut a mould into a block of plaster.
For more complex and deeper shapes, the design can be digitally sliced into segments to create a mould, which are 3-d printed. Plaster is poured in to make the master, and then the mould parts are plaster cast off the master (you cannot just use the plastic 3-d print mould, as it needs to be porous). Once the mould has been cast in plaster, it is ready to use. The steps in this process can be seen in Fig. 1, showing work by Tony Hansen of DigitalFire. Alternatively, 3-d printers that can work directly with clay are becoming more common, though these cannot offer as much detail as printing in plastic and taking a mould from the plastic.
But, of course, work need not just use clay. At its simplest, wooden parts can be added to create a plinth, a lid or a handle. Or be more experimental with firings: classic examples are to use coloured glass, or metals in the form of anything from filings to coins, or anything from fine sand to small pebbles. Sprinkle any of these on top of your glaze, and see what happens, using some PVA adhesive to hold them in place until fired if necessary. But don’t do this on pieces that may be used for food or drink, and if there’s any chance of the glaze running onto the kiln shelf put the piece onto a saucer to protect the kiln shelf. Some of these experiments may be more successful than others, so whenever possible do tests in a small bowl before using on a pupil’s finished work, unless they’re happy embracing the risk of an unexpected outcome. Fig.2 shows a bowl by David Burns, incorporating ceramic sherds from some tableware and porcelain doll parts; Fig. 3 shows a ceramic painting by Lotte Glob, using locally found sand and pebbles as well as glaze.
It's worth building up a gallery of test result, perhaps all mounted on a wall. Not only of tests like those suggested above, but of your different clays and glazes. This should show the same glaze on different clays, applied at different thicknesses. Then extend this to show the effects of layering two different glazes on each other, to see how they interact. Try and put a few test pieces into each firing to build up your collection. This will show students what they can achieve, and help them decide on the finish they want. Also, in doing this it’s important not to just pick clays and glazes at random, but to match them to each other and to the temperature you fire your kiln to – something that’s covered in my Kilns for Schools course.
Fig. 2: David Burns
Bowl with porcelain doll parts and sherds of blue and white porcelain.
If your pupil wants to incorporate some artwork that is already in a digital format, or would be excessively complex and time consuming for them to paint by hand, then they can create a JPEG image of the artwork (allowing for any curvature on the surface of the piece), and then companies like Digital Ceramics will convert it to a ceramic transfer that you just dip into water and slide onto a (normally white) base glaze on the piece, then fix it in place with a low temperature firing. Fig. 4 shows this in a piece of mine, with a wood and canvas section of a WW1 plane, and tiles for the viewer to rotate with ceramic transfers showing on one side the official views of the Royal Flying Corps, and on the other the realities of being a pilot.
But, of course, all this tech can get in the way of another aspect of clay – because it can just be pushed and pressed into shape by hand, it can be great for immediate emotional expression, particularly for things that the child cannot or won’t express in words, for example if they don’t feel in a safe place with the staff or other children around them, or they’re traumatised from events like having been sent off to boarding school at a young age. The resultant piece may not be recognisable or explicable, but this immediacy of clay is something that shouldn’t be lost, helping children come to terms with their emotions.
Fig 3: Lotte Glob.jpg
Glaze and rock ceramic painting using glaze, sand and pebbles
Fig 4: Tim Thornton.jpg
Ode to the RFC. Wood and canvas fuselage, with rotating ceramic tiles with ceramic transfers fired on
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