Wedging

Wedging is a process of kneading clay through a combination of lifting, pushing and pivoting the material. There are subtly different methods of wedging – ram’s head, spiraling lotus, cone - that are named after the patterns that arise from the movement of one’s hands. These movements can feel complex and uncomfortable (1) but after a period of regular practice, they emerge from one’s body as a fluid gesture; a gentle force that has a reciprocal echo in the clay body that seems to roll back into one’s palms after every push.

Wedging is often cited as essential because it releases air pockets that may be hidden in the body. Air expands rapidly when heated to high temperatures in the kiln; if trapped, this air will rupture carefully-made forms in their attempt to escape. But wedging prepares clay to become, long before it enters the threshold of the kiln.

The hallway is a rush of people updating each other boisterously about their weekend plans, walking briskly to their next meeting, scrolling through their phones while waiting for their lunch order, pushing carts filled with cleaning supplies or the day’s package deliveries. Amidst the flurry of activities, someone is crouched on the ground in a narrow strip of rectangular space that slices through the exhibition hall and wraps around a concrete pillar. She is bent over and moving both hands slowly and methodically on the ground. It is hard to see what she is doing from a distance. The area has been laid with bare plywood and partly covered in glossy tiles. There appears to be a gap in the wall that cuts through the area, and a partially-built wall with jars of water and balls of vividly-coloured material stacked on the studs. Some passersby cast a curious glance, but many do not notice.

A wall label reads, ‘Construction and renovation is almost ceaseless in urban cities today. This 40 hour performance explore what maintenance is through the properties of clay.’

(1) Push down on the ball of clay with the heel of both palms. Hold both sides of the clay firmly while doing so to prevent the clay from becoming too elongated. Lift the back of the clay ball slightly with your fingers and push the clay with the heel of your palms from the two sides down toward the center of the clay again. As you repeat these motions, the ball of clay will begin to spiral into itself from both sides creating a form similar to a ram’s head. The indent created by the palms should not be so deep as to create a hollow where air can be folded into the clay, but enough pressure should be applied so that hidden air pockets in the clay can be released. A ball of clay that can be held comfortably by both hands needs to be wedged a minimum of two hundred times.

Clay is formed by minerals that are eroded from the earth’s crust by forces of wind and water. These mineral plates are held together by a capillary force (2) that gives the necessary cohesion in a clay body. Mineral plates in unprepared clay is often partially disordered. When I touch it, it wants to crumble apart even with sufficient amount of moisture present. But I am not afraid; I hold the clay body firmly and fold it into itself repeatedly until the process brings the mineral plates into alignment. Then it becomes pliant and cohered in my hands.

There are several balls of dark clay laid on the ground. Each one is carefully brushed with water and covered with a damp rag. After resting in moisture for some time, they are each taken out and kneaded. She leans forward with her body weight with each push. She leans back slightly with each lift and turn of the ball of clay. Push, lift, turn, push, lift, turn, until the movements blur into a steady rhythm that seems to sustain itself. The clay is the colour of coal or tar. They leave shadows of their movement stained on the plywood floor. “It’s a lot of work,” someone murmurs as they pass through the hallway.

Clay has a persistent, hidden memory. When I reshape a clay form, it remembers its past. Clay that is prepared commercially in the pugmill and packaged into rectangular blocks will remember its edges. Without the wedging, ghosts of previous forms may emerge during the drying or firing process, creating cracks in even the most finely finished surfaces.

(2) Capillary force can be explained by the following comparison: Two pieces of flat glass are placed on top of one another with a little bit of water in between. The two parts can slide around, but they can’t easily be separated as a strong force, the capillary force, holds them together.

A dark, soft matter has gathered on the ground around the pillar. Its surface is dimpled and sometimes marked with longer grooves. There’s a bucket of grey water at rest nearby and long, dark coils laid out on a piece of stained cloth.

Cracking

When working with clay, an enormous amount of labour
and attention is dedicated to avoiding the emergence of cracks during the building and drying process. The causes of cracking can include but are not limited to: a lack of plasticity in the clay body, a lack of cohesion in the clay body, insufficient moisture, sudden shifts in the thickness of clay, letting clay drying too quickly or unevenly.

If a crack is caught when it’s tiny, it can be smoothed out with fingertips. If a large crack appears, moisten with water, wedge the entire form back into plastic state and start again from scratch. If a surface repair is made, the crack will likely reappear once water escapes from the body. Sometimes despite wedging, joining, supporting, smoothing, moistening, covering, checking, waiting, clay bodies can still crack or fragment upon drying.

Cracked clay can be soaked in water and reworked into a plastic state, even after it become bone dry.

Cracks have begun to creep towards the pillar from the outer edges where dark, black clay has turned grey. Rich, orange clay is rolled gently into long, pliant coils with both hands. From time to time, she dips her hands into a bucket filled with orange-coloured water, and runs her fingers along the coils, leaving them wet and shiny. When a number of coils have been accumulated, they are laid out along the outlines of past layers of clay. Sometimes the coils are smoothed out with fingertips, each press and pull of skin on clay closing the gap between the coils until they come a spread of dimpled orange. Other times, the coils are smoothed out with feet, soft wet clay giving way easily to the weight of a body, spreading outwards to bridge the gap between the tide of clay and the pillar.

The narrow space is a smudge of charcoal black and vivid orange in the empty hallway of polished concrete floors, stark white walls and high ceilings. Cracks have woven their way all around the ground surrounding the pillar, branching outwards in a centripetal pattern, as though the pillar has suddenly acquired a life-force. Where clay touches the white tiles, slip begins to fill the gaps between them. Rich orange and dense black spill out from the grid of shiny tiling. Someone is on their hands and knees filling in the slip and wiping away excess with a wet rag. The water bucket becomes murkier and murkier. Orange and black smear across the ceramic surface, at times almost obliterating the grid. She rinses and rinses the rag in a bucket of water, but the vivid colours stain everything – the water, the rag, the apron and shirt she is wearing, the skin on her hands and feet.

“How long more do you have? Can you finish it in time?” someone asks.
“I am doing this for five days,” she replies.

Staining

Clay bodies, taken from the earth, contains large amounts of minerals that can give them potent staining strength. One of the most common naturally occurring minerals in clay – iron oxide – gives bodies a rich red, black or yellow colour. Most ceramic studios have separate work surfaces for staining clays because their colours seep into almost any surface it comes into contact with.

These bodies resist the desire to keep things clean and contained. Wherever they touch, they leave an echo of the earth. I begin to notice the shadows of wedging movements on plywood surfaces, the outlines of slips that linger on plaster slabs longer after I have removed the clay.

When I spend a day in studio working with clay bodies rich in iron oxides, the sink gradually become filled with bright orange (3) as I wash my hands, clean my tools, and wring out of rags that are dyed burnt orange.

(3) Clay studios usually have sinks with clay traps to prevent clogs. Clay particles suspended in water will sediment and separate
from water if left undisturbed overnight. This allows one to trap and recycle the clay. If working in an area with no running water, one can use three separate water buckets for clean up, gradually progressing from a murkier to a clearer bucket during the washing. Let buckets that are murky sit for several days, and clay particles will sediment, allowing clear water to be poured off the top. Both water and clay slip can be reused.

The clay has spread from edge to edge in the slice of space. It seeps through the partially built wall and emerges on the other side, spreading until it runs out just before it touches the edge of the ceramic tiles. There’s no more clay stacked on the wall studs. Every jar of water has turned a shade of orange, brown or grey. Nearly all the clay has cracked. Some fissures are so large, the stained plywood beneath is visible; other cracks are a fine web, impossible to discern where it begins and ends. Some of the cracks have been repaired with orange clay. She rolls out a thin coil of clay between her palms, carefully applies water to the crack with a brush, lays the coil in the crack and smoothes it out with her fingertips. But even that has begun to crumble as water escapes.

Much of the dried surface has been peeled away, leaving only crack lines mapped by orange dust and a plywood surface with deeply stained tree rings. There are stacks of clay fragments laid out on the ceramic tiles now smeared with traces of orange and black. She dips each stack of clay into a bucket of murky water, and breaks them into small pieces on a damp rag. When a mound of tiny fragments have been accumulated, she pours them back into the water bucket to soak.