Making a Clay Monotype Paul Andrew Wandless

Appears in the Jul/Aug 2017 issue of Pottery Making Illustrated.

Monoprinting is a printmaking method that yields a single (mono) original print using a printing plate, ink, and paper as the core supplies. The imagery is created on a flat printing plate (glass, Plexiglas, or metal) with oil-based ink. A sheet of damp paper is laid on top, covering the entire image. The ink is transferred from the plate to paper through pressure using a press or burnishing by hand.

Monoprints vs. Monotypes

Not all prints created using the monoprinting method are called monoprints. How the imagery is created on the plate determines which one it’s called. If some or all of the imagery was created using another printmaking method (screening, relief, stencils, etc.) on the printing plate, its called a monoprint. If all the imagery is hand drawn or painted on the printing plate, its called a monotype.

Clay Monotypes

The monoprinting process for clay prints is the same as it is for paper prints, with the notable exception of working with different core supplies. A plaster bat is used as the printing plate, underglaze is used to create the imagery, and clay (or casting slip) replaces the paper used to pull (capture) the image off the plaster bat.

Key Factors in Creating Imagery

There are a few key factors to remember when creating imagery on a plaster bat that will make your image successful. The first is composition (arrangement of your subject matter). The monoprinting process reverses the composition of the image. Shapes and designs on the left side of the printing plate will be on the right side of the clay print. Any text or numbers used will be reversed as well.

The second factor is the order in which the layers of color are applied. You work from foreground to background when making a monoprint. So the choice of opacity and transparency for the colors used are important. When overlapping layers of shapes or lines, the first layer of information will appear in front of any subsequent layer placed over top. Knowing you have to work from front to back when layering can be used to your creative advantage. If you first make a shape with a transparent color, then you will see the overlapping color in the transferred print. Making transparent layers of shapes and lines can build a richness of color and depth.

The third factor is the casting slip used, which can affect the contrast and temperature of the transparent colors used to make the print. The image created is usually a combination of transparent, opaque, and uncolored areas on the plaster bat. The casting slip becomes your background color choice for the image. Dark clay bodies (earthenware, terra cotta) can mute and neutralize the transparent areas while light clay bodies (porcelain, talc bodies, stoneware) can brighten them up. Use the clay body as one of your color choices and purposefully leave open areas in your image so the clay can be exposed. So, if I use a brown casting slip, I can leave areas of my image open where I want that color of brown.

Under Drawing

Your image or design can start as a pencil drawing. Draw on your plaster bat like a sheet of paper using a dull graphite pencil (2H or 4H pencils work best). This is referred to as an under drawing (1). Avoid pressing too hard or using a sharp pencil as this will scratch and scar the plaster surface. A damp sponge, can remove errant marks. Any graphite that transfers with the underglaze to the clay print will burn away without a trace when kiln fired.

Once the underdrawing is complete, you’re ready to apply your underglaze and colored slips. You can use assorted sizes of brushes and slip trailers to apply the color with a nice variety of line width and mark making. I typically use a slip trailer and small brush to go over my line drawing using an opaque black underglaze (2). If you don’t want any outlines, simply use the drawing as a guide when applying color to your image.

Tools: Brushes, Slip Trailers, Colors

Trying to make one brush fit all your aesthetic needs isn’t always the best practice. The quality of line you make depends on your brush selection. The more conscious you are of this, the better your imagery will be for your final print. A basic set of brushes for water-based media will give you a good variety of line and fill options. The brushes I recommend having are a round, pointed round, detail round, flat, fan, mop, and a hake (A).

All kinds of things can be used as a slip trailer. Trailers are typically used to make lines of varying width with clean edges. You can choose from a wide variety of commercial bulb trailers, bottle trailers, and syringe trailers. The size of the orifice determines the thinness or thickness of the line. Since a trailer is a container that holds up to an ounce or more of liquid, you can make a longer continuous line than with a brush that needs to be reloaded (see A).

Watercolor underglazes, underglazes, and colored slips can all be used when adding color to your image (B).

Coloring in Layers

Start with transparent colors first before adding opaque ones. If the first layer of shapes or lines are opaque, then nothing will be seen through them. No other layers should be applied over that particular area. Start with the watercolor underglaze where you want an ink wash effect (3, 4). Next, use transparent underglazes to build layers of color that can optically mix (5). Apply the opaque slips last (6). As you add color, you can also do more drawing as well and let the image continue to develop. Just remember that the first layer you put down becomes the  foreground.

You can also take a coloring book approach and not layer anything at all and fill in all the areas and shapes with your desired colors. Since all the colors are placed next to each other, there’s no need to worry about confusing the order of your layers and how the transferred print will look. If you’re new to monoprinting, this is a good way to make your first print as you learn the overall process.

Casting and Pulling the Clay Monoprint

Once the design is dry to the touch, you’re ready to cast the print. You can do this right away or months later—once the slip is poured over the image though, all the normal clay set up times must be observed. Since this monotype has layers created with underglaze watercolors and transparent underglazes, apply an opaque white underglaze over the entire image (7). This white background will help in retaining the color and adding brightness. If all the areas of your completed image are opaque, you don’t need the white background layer.

To prepare to cast your image, first be sure the plaster bat is level. If this isn’t done, one side may be thicker than the other. I like to have the bat elevated on two strips of drywall. This allows air to pass under the bat to help dry the bottom.

Next, roll out a ¼-inch slab and cut it into 1-inch strips to make retaining walls around the perimeter of the plaster bat. Brush casting slip on one end of the  1-inch tall clay strips, then place them (slip-side down) around the perimeter, pressing firmly and connecting the ends to create a secure seal (8).

Mix your casting slip a few minutes before using to make sure its a nice even consistency. Choose a corner to start slowly pouring and let it spread and fill the mold box until it’s between ³⁄₈–½-inch thick (9). Depending on the shrinkage of the casting slip, this will give you a finished thickness of ¼–³⁄₈-inch for the clay print. If your casting slip is on the thick side and doesn’t level out on its own, you can smooth the top with a plastic or metal squeegee or spreader.

Once cast, the liquid casting slip rehydrates the underglaze and colored slip, allowing the image to be absorbed (transferred) and captured in the stiffening clay.

When the cast slab is firm to the touch, cut and remove the clay retaining walls from the cast slab to allow the clay to dry from the sides (10). The cast slab can be removed from the plaster bat when it reaches the early stage of leather hard. Small prints under 12 inches can be pulled up by hand. For larger prints, put a piece of drywall on the cast slab, flip it over, then carefully lift off the plaster slab.

Typically, a little color is left behind in the plaster bat that wasn’t completely absorbed and transferred (11). This residual image is referred to as a ghost image and can be wiped off with a sponge and water. Once you have your clay monotype pulled, you can trim the edges to square up the print. To help it dry flat, place a piece of drywall on it until it’s bone dry.

Once your plaster bat is dry from being cleaned with water and a sponge, you can make another image. The second monotype is always more successful since you understand the process of using layers to your advantage. If you like to draw and paint, you will love this process of making clay prints.

Paul Andrew Wandless currently lives and has his studio in Chicago, Illinois. Wandless has authored the books Image Transfer On Clay, 500 Prints on Clay, co-authored Alternative Kilns & Firing Techniques, and is featured in the DVD Fundamentals of Screen Printing On Clay with Paul Andrew Wandless available on Ceramic Arts Daily. To learn more, check out www.studio3artcompany.com.

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