Deep Layers, High Surfaces Scott Jelich

Appears in the Jan/Feb 2015 issue of Pottery Making Illustrated.

I make pots that bring together a range of influences, while the surface textures and colors I use to decorate my pots are largely influenced from the landscape of South-central Alaska where I grew up. The earth tones and colors produced in combination with the coarse texture of the iron-rich stoneware creates a tactile variation in surface that invites touch and interaction.

The process of using vinyl-decal printing is a simple way to create multiple stencils that can be used as a resist alternative to wax or latex methods. Not only does the vinyl work as a well as these other resists, but it also adheres to the bisque surface well enough to allow for sandblasting. The sandblasting causes the surface around the stencil to erode and recess. Once fired, the effect is an inlaid glaze pattern that is level with the bare stoneware pattern/surface. This inlaid decoration came from my interest in  the marquetry decorations of early American furniture and cabinets, specifically those produced during the Aesthetic movement of the late 19th century.

Using a Vinyl Cutter

I begin by sketching a simple branch and leaf pattern with a flower to create a template. These drawings are then transferred to tracing paper. I try to keep my designs and patterns fairly simple so they can be cut and manipulated easily. I scan the image then manipulate it in a drawing program such as Adobe Illustrator or the program provided with the vinyl cutter.

Printing the designs using the vinyl cutter is a fast and efficient way to produce personal decals. My vinyl cutter is a 12-inch Silhouette Cameo plotter and I use a high-tack vinyl so that it will adhere to the bisqueware enough to withstand the sandblasting. The rolls of vinyl and transfer paper come in different sizes, colors, and tack or stickiness. You can purchase this material online from many different sign-making supply stores.

After the decals are printed, the surrounding waste vinyl needs to be removed so only the decal design remains. I then place a clear transfer sheet over the decal page that will be later used to lift and stick the decals on the piece (figure 1). Using the transfer sheet may not be necessary depending on how intricate the design is. I use it for ease of application so the vinyl doesn’t fold over itself and stick together.

Next, I begin composing a design on a bisque-fired pitcher by placing decal sections onto the piece and using an X-Acto knife to cut and trim the decals to size and occasionally layering the decals to make the plant decoration larger and flow around the pot (figure 2). Be sure the decals are fully adhered to the pot before moving on.

Sandblasting

Once the design is finished, it’s ready for the sandblaster (figure 3). I like to use a finer mesh size of blasting media, 80-mesh silicon carbide, with around 55 psi of pressure in the sandblaster. The finer mesh material will etch the bisque surface without tearing up the vinyl decals. A larger mesh size or different material may eat though the vinyl, destroying the decoration. Depending on your sandblasting media, you may have to adjust your psi higher or lower on the machine you are using. I recommend using a test piece first to ensure the vinyl won’t be blown off the surface of the piece or be destroyed.

I carefully sandblast the surface going around the design so the surface around the decoration recedes down to about ¹⁄₁₆ inch (figure 4). Because I fill in the unmasked areas with glaze, I try to estimate how thick my glaze application needs to be because I want the glaze and the masked surface to sit on the same surface plane.

Once I’ve thoroughly sandblasted around the masking and all the areas around the vinyl are evenly recessed, I use a compressed air hose to remove residual dust from the sandblasting and then gently wipe down the surface with a damp sponge and clean water. Removal of dust and debris is very important or the glaze won’t adhere properly or could potentially crawl off the piece during the firing.

Glaze Application and Decal Removal

After the piece has dried from the cleaning, I line the pitcher with cone 10 glossy white glaze and then dip the entire pot in a cone 10 satin-matte glaze to coat the exterior (figure 5).

Next, I begin to remove the vinyl stencils. This should be done shortly after the glaze dries, as the glaze chips less when there is still moisture in it. I use the sharp tip of the X-Acto knife to carefully peel up the vinyl pattern (figure 6). Caution: Wear a respirator during this part of the process because the excess glaze on the vinyl can create dust as you are removing it.

I work my way around the pitcher until all the vinyl is removed (figure 7). Occasionally glaze chips off in the tighter areas and needs to be reapplied to keep an even coat throughout. Some glaze smoothing in areas may also need to be done. Caution: When smoothing the glaze wear a respirator and work in a well-ventilated area. Now the pot is ready to be fired.

Notes on Firing

I generally fire my work in a gas kiln, reducing heavily for an hour at cone 010 and then a light to medium reduction for the rest of the firing until cone 9 is down and cone 10 is barely soft. This type of firing gives me a dark brownish to an almost purple color from my iron-rich clay and softness in my glazes without making them too shiny.

Scott Jelich earned his BFA in ceramics from the University of Alaska Anchorage in 2012, then spent a year attending the University of Montana as a post-baccaulaureate student. He is currently an MFA candidate at New York State College of Ceramics at Alfred University. To see more of his work visit www.scottjelichceramics.com.