Impressions, Imprints, and Dipping

If an absorbent organic material such as cotton fiber or woven fabric is dipped into slip (liquid clay) and then fired in a kiln, the organics burn away, but what is left can still resemble the original in shape and texture. Controlled press-molding can also give the illusion that the organic material has been transformed rather like the formation of a fossil.

1 Cut and twisted bamboo window blind.

2 Hanging the bamboo blind from the ceiling enables the structure to become a free-flowing form.

3 Applying the clay slip in layers on the bamboo blind. Each layer is left to dry before applying the next one.

 

Wave Forms Using Bamboo

The marks left after the firing are rather like an impressed memory, explains Danish ceramic artist Mette Maya Gregersen. She draws a parallel with our lives as humans, “Life experiences change us, leaving lasting marks, but the solid moment of experience is gone forever.” Mette exhibits her sculptures in her homeland, Denmark, and the UK. Collecting fleeting impressions on her travels has always been part of Mette’s life and she says that this search for meaning has found its expression in her wave work. The wave shapes are held under tension during their formation and she captures this energy in the firing.

She uses sections of bamboo window blinds, which she cuts up, then ties with thread and wire into curved, wave-like forms (1), and hangs from the ceiling to create a free-flowing form (2). Soft stoneware clay, with additions such as molochite, paper pulp, acrylic fibers, bentonite, and sand, are then spread onto one side of the form and allowed to dry (3). This procedure is repeated several times until the required thickness has been achieved—a slow process that takes several weeks. A bisque firing to 1472°F (800°C) takes place in an outdoor gas kiln, because lots of smoke is produced from the burning bamboo (4). Any residual wood ash is brushed off before a second biscuit firing to 2084°F (1140°C) in an electric kiln.

Finally a range of glazes are applied to the curved forms, with repeat firings on many occasions, until Mette is satisfied with the depth of surface achieved (5). Glaze firings go up to 2336°F (1280°C).

4 The pieces are fired in a gas kiln outside, as there is a lot of smoke from the wood.

5 Often the pieces are glazed several times, and fired many times, in order to obtain depth in the surface.

 

Honeycomb Forms Using Cotton Fiber

The objects made by Katie Queen are her own inventions, but they resonate with details from the world around us. A seedpod, or the delicate connection between a berry and its stem, are examples of what Katie calls, “the minute perfection of nature.”

6 Porcelain casting slip is poured into the mold and allowed to sit until the thickness is right.

7 Once the castings have become leather hard, they are easily removed from the mold.

8 Cast forms have been cleaned, scored and joined together to create the desired form.

 

Porcelain is her chosen material, coiled, slabbed, and press-molded using custom–made molds, extruded or thrown on the wheel (6–8). The method depends on the design of the piece. She uses organic cotton fiber on some of her work. While the form is leather-hard, balls of cotton fiber, partly dipped in deflocculated slip (9), are attached (10, 11). The organic material burns away in the bisque firing (1872°F (1022°C)), leaving a hollow cavity that Katie likens to a honeycomb or a barnacle. Sometimes she fills this cavity with dyed polyester fiber (12).

9 Cotton fiber is dipped into casting slip, only half to three quarters of the way up, to allow a cavity to form.

10 Dipped cotton is attached to the cast form.

11 Complete form with cotton fibers attached, ready to be bisque-fired upside down.

12 Katie Queen’s Objected Blue, 18 in. (46 cm) in length, press-molded and coil-built porcelain, polyester fill, fired to cone 10 in oxidation, 2004.

 

Knitted Tableware

Helen Gilmour’s work explores the connection between ceramics and traditional crafts such as knitting and crochet. She deconstructs functional pottery by soaking cotton yarn in porcelain slip to produce knitted, non-functional ceramic vessels. She began experimenting with these materials while studying at the Glasgow School of Art and has continued to develop this work, improving her techniques and seeking new possibilities. Her ceramics appear delicate but are strong enough to be handled and transported.

Process

The first step is to knit the pieces—teacups, saucers and teapots—using 100% pure cotton knitting yarn. They are then thoroughly soaked in porcelain slip and wrung out several times before being stretched over a former and left to dry (13). Inflated balloons work well as formers for teapots. More slip is applied while the form is still on the balloon via spraying, dipping, and painting (14). Through experience, she knows when the right amount of slip has been applied in order to produce a finished piece that will be strong enough to handle, but still clearly reveal every stitch of the knitting. This process can take several days.

13 Stretching soaked knitting over balloon former.

14 Applying more slip while still on balloon.

 

Helen describes the removal of the balloon, “I wait until the piece is properly dry and stiff before removing the balloon. If it hasn’t already started to deflate, it is best to remove it by letting the air out slowly. Sticking some tape on the balloon and making a small hole through it prevents it from bursting.

“The work is extremely fragile at this stage and great care must be taken while handling it, avoiding any damaging bumps or dents that might affect the strength of the pot.”

As the teapot was knitted without a base, the next stage is to form the base and attach it to the teapot. Paper clay porcelain is rolled out thinly onto a plaster bat to form the base. The clay picks up the knitting texture on the cast plaster and is then cut to size (15). The base is joined with slip to the teapot body when they’re both bone dry. Helen says that, in her experience, the shrinkage of both the porcelain slip used on the teapot body and the paper clay in the base is the same, so cracks are avoided.

15 Cutting out the base made from flax paper clay.

16 Helen Gilmour’s teapot, 8 in. (20 cm) in height, knitting soaked in porcelain slip, 2011.

 

The work is fired to 2336°F (1280°C), with good ventilation while the cotton burns out. Slumping can occur at these temperatures, which can enhance a piece, but where it’s not desired she takes care to try and avoid it. For this reason, when making teapots, she adds the spout and handle after they have been fired (16). Smaller pieces such as cups and jugs are often fired upside-down with their handles attached, allowing the slumping to compliment the form.

Excerpted from Additions to Clay Bodies by Kathleen Standen, available at https://ceramicartsnetwork.org/shop.

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