The Enduring Quatrefoil Juliane Shibata

Appears in the Jan/Feb 2023 issue of Pottery Making Illustrated.

I’m fascinated by the varied ways cultures of different eras have used pattern and ornamentation. The word quatrefoil comes from the French word quatrefeuille, meaning four leaves. The shape has been found on Mesopotamian pottery shards dating back to the Neolithic period and is believed to have spread across the globe through persimmon traders; the fruit’s sepals are made up of four distinctive leaves.¹ The quatrefoil pattern appears on Mayan monuments,² can be observed in Gothic architecture, and is recognizable on everything from rugs and shower curtains to designer handbags today. 

I was initially drawn to the familiarity of the quatrefoil motif, but also fell in love with the negative spaces created when repeated shapes are laid out in a grid, which in turn allows for better control of the negative space when installing in multiples. By cutting multiple quatrefoil tiles out of clay slabs, I began to integrate three-dimensional pattern with two-dimensional painted motifs atop the four-lobed tiles.

Clay Body Considerations

After experimenting with six different high-fire clay bodies, I have found that both Continental Clay’s Grolleg Porcelain with Nylon Fiber and stoneware clay have performed best in press molds. Tip: Adding ½-inch-long nylon fibers to a clay body can help prevent cracking and give your clay body more working strength through the forming and drying process. If you choose to add nylon fiber to a clay body, you only need a small amount. Recommendations range from adding 0.25% to 2% nylon fiber by weight to dry clay mix. Nylon is a form of plastic, so even though the nylon is present in relatively small amounts, proper ventilation during bisque firing is recommended.

Technical Challenges

The quatrefoil is one of the more challenging shapes I’ve explored. Designing the form itself has been a continual process; I’ve experienced multiple failures and have had to troubleshoot and adapt. Porcelain is prone to warping and cracking and the quatrefoil is especially troublesome due to the tension in the lobed structure; hairline cracks can easily develop at one or more of the four corners. I learned this the hard way when I made my first installation piece with 20 quatrefoil-shaped porcelain tiles created from hand-rolled and hand-cut slabs. The majority of the tiles cracked in the high-temperature glaze firing. Adding epoxy to the cracks and covering them with gold leaf made the mended tiles more visually interesting, but while there can be beauty in imperfection, I have continued testing to try to minimize the cracking issue.

Homing in on the Right Shape 

The template I use to make the quatrefoil slabs has undergone three different iterations since 2019. The first template, hand drawn and 8½ inches in diameter, wasn’t perfectly symmetrical. Seeking a more exact geometric form that would minimize idiosyncrasies from one tile to the next, I made the second template by sizing a digital image to the desired scale and printing it out. The most recent template is fairly similar to the second in shape but slightly larger and made out of wood cut with a laser cutter. Aaron Heidgerken-Greene, the Instrument Project Manager of Carleton College’s Makerspace (Northfield, Minnesota), suggested we implement a more rounded curve where the edge of the lobe meets the central area of the form to reduce stress on the clay, and this has indeed resulted in fewer failures.

Locating a Laser Cutter

If you are interested in using a laser cutter or engraver (the latter has a lower-power laser3) to make a mold or another tool for a ceramic application, try looking for makerspaces in your area that have the equipment you seek. You might start by visiting makerspaces.make.co, an online directory, to search for centers, or ask around. All makerspaces are different, but some may allow you to join for one month (rather than a longer period) if you have a specific project in mind. Fees vary but typically run $50–60 for a month of access. 

You could also try calling Joann Fabric & Crafts Stores. Select locations carry the Glowforge, a 3D laser printer that can both engrave and cut a range of materials; you can rent the machine for $15 an hour at the retailer. The representatives I spoke with recommended that people view some how-to videos on Glowforge’s website (www.glowforge.com) or YouTube before coming in to use the machine, and that it may be worth calling ahead to find out when a staff member familiar with the equipment will be working. Glowforge accepts a variety of files (i.e. png, jpg, pdf, svg), and files used with Cricut or Silhouette cutting machines are usually compatible. If you’re not savvy with digital files, ask someone who is more familiar working with them to help troubleshoot or search out how-to videos online as you explore the possibilities.

Wooden Press Mold

After continuing to alter my approach with various methods to prevent cracking in these forms, I still wasn’t getting consistent results, even when drying the slabs slowly over month-long periods. Donovan Palmquist, a Minnesota studio potter and kiln builder, suggested that I try making a mold for these forms instead of cutting them out of a slab of clay with a fettling knife. With Aaron’s help, we used a laser cutter to make a wooden press mold that forms a slab into a quatrefoil that is 3/8 inch thick and 9 inches in diameter. Aaron suggested I use ¼-inch birch plywood for my mold because it cuts well and is cost-effective. This mold consists of a wood base and an outer ring in the shape of a quatrefoil (A). Because the ring is secured to the base by magnets (which are set into the wood), it can be separated from the base during use to release the final molded form (B). Tip: Different laser cutters have varying cutting capabilities depending on the material used. The laser engraver used to make my quatrefoil wood mold was a Universal Laser Systems PLS6.75. 

Forming

To form a quatrefoil tile, begin by placing a sheet of printer paper on the base of the mold and attach the outer wooden ring (1). Pound out a slab of clay and begin to flatten it, flipping the slab occasionally to compress both sides. Next, place this thick, compressed slab over the top of the mold and pound from the center of the mold outward (2). Cut off any excess clay with a wire tool (3). Use a rib tool to smooth the back of the slab (4).

To release the form, lift up the wooden ring (5). Place a second sheet of printer paper on top of the newly released slab. Find a flat board and place it on top of the paper and slab (6), then flip the slab over and remove the base paper (first piece). If needed, use a rib to smooth the top surface lightly (7). Cover the piece with a perforated plastic sheet (8).

After waiting 24–48 hours, remove the paper sheet from the bottom of the slab and replace it with a fresh one to prevent a wrinkled texture from developing on the underside as the clay shrinks; re-cover the slab with the same sheet of plastic.
With the new paper sheet in place, wait another 24–48 hours and then remove the paper underneath the slab altogether; re-cover with the sheet of plastic.

When the slab is firm enough and doesn’t bend easily, bevel the bottom edge with a fettling knife (9).

Thoughts on Slow Drying

Make sure the surfaces you lay your pieces on are flat. I dry my quatrefoil tiles on Continental Clay’s ¾-inch-thick Hydra Bats or ¾-inch-thick drywall boards. Drying the slabs evenly and slowly can help prevent unequal stresses on the clay. Using a needle tool or toothpick, I pierce evenly spaced holes (about ½ inch to 1 inch apart) in a plastic sheet and drape the plastic over the wareboard that the clay is resting on. I then tuck all plastic edges under the wareboard to prevent uneven drying around the outer edges of the form. Even when covered with plastic, be careful to keep the slabs away from any strong source of air flow, such as a vent or fan. When the slabs are at the edge of bone dry, I bisque fire them, starting with a preheat to remove any additional moisture from the clay.

Decorating the Surface

I am drawn to the accessibility and ubiquity of textile patterns. As an artist of mixed heritage, it’s meaningful to me to work with a range of historical patterns from both Eastern and Western cultures. Quatrefoils explores motifs from both the Arts and Crafts movement in England and the Mingei movement in Japan.

After the pieces come out of the bisque firing, I begin by loosely laying out an initial design on a tile with a graphite pencil, often using my collection of textile and pattern books for reference (10). I then use underglaze applicators and/or brushes to apply color and occasionally draw with underglaze pencils to enhance the decoration (11). By working with a variety of Chinese underglaze brushes, craft brushes with natural hair, and a large color palette, I can establish a wide array of marks in varying hues. When I feel the underglaze design is complete, I often pour a transparent glaze such as celadon or clear over the tile to create more depth and intensify the underglaze colors (12). I work with several types of underglazes, including some acquired in Jingdezhen, China, years ago. Using underglaze is a bit like working with watercolors: the amount of water that is mixed with the material affects how saturated the color will be. Multiple washes layered on top of each other can also increase the richness of color.

Mounting 

In order to give my tiles the illusion that they are floating off the wall, I epoxy a few ceramic cubes to the back of each piece after the glaze firing. The first cube is attached at the top of the back of the tile (13). I use PC-11 epoxy to affix each cube. The top cube has a small hole drilled into it, through which I loop a 22-gauge, tarnish-resistant wire so that the piece can hang from a small nail. Add two other cubes so the tile will balance evenly on the wall and wait for the epoxy to set before hanging (14). I add the cubes post-firing to avoid stressing and warping the work in the cone-10 glaze firing.

As ceramic artists, we experience the highs of seeing good pieces come out of the kiln, but we also experience the struggles and disappointment of failure when inevitable technical issues occur. Be persistent and take heart. Take notes when problem-solving to identify what you’ve done and what approach you might try next. Avail yourself of the collaborative and generous spirit that defines this field by asking other makers and designers for their ideas and perspectives, knowing that every setback and triumph will also be part of your contribution to the world of ceramics. 

Juliane Shibata is an artist and educator from Northfield, Minnesota. She creates large-scale installations that consist of numerous repeated handbuilt forms, as well as individual wall pieces and functional work. She is represented by Abel Contemporary Gallery in Stoughton, Wisconsin, and Gallery 360 in Minneapolis, Minnesota. You can see more of her work by visiting www.julianeshibata.com.

1 Tikhonova, Elena and Dmitrii Tikhonov. “The quatrefoil motif and its probable origins in Sakha folk ornamental art.” Siberian Research, vol. 5, no. 1, 2021, p. 53. DOAJ Directory of Open Access Journals.

2 “Quatrefoil.” Wikipedia, Wikimedia Foundation, accessed September 21, 2022, https://en.wikipedia.org/wiki/Quatrefoil.

3 Abraham, John. “Laser Engraver vs. Laser Cutter—Are they Different?” MellowPine, accessed August 23, 2022, https://mellowpine.com/cnc/laser-engraver-vs-laser-cutter.