How to Create Surface Designs with Tape Resist, Underglaze, and Terra Sigillata Michael Griffin

It can be very difficult to find your voice in pottery. For Michael Griffin, it took years of experimentation with a wide variety of techniques. Finally a switch from the wheel to handbuilding and away from glazed surfaces made it all click into place.

In today's post, an excerpt from the February 2023 issue of Ceramics Monthly, Mark shares how he builds up surface design with terra sigillata, underglaze, and tape resist. –Jennifer Poellot Harnetty, editor

PS: To learn how Michael handbuilds his teapots, check out the February 2023 issue of Ceramics Monthly.

Surface Decoration Process

My surface decoration process includes a bit of everything. I use a homemade terra sigillata to create a matte surface that looks rough, but feels much smoother than it appears in pictures. I also use paper resist, wax, and sometimes underglaze after the bisque firing. 

First, the pot has to be very dry, which I learned when starting to use terra sigillata by cracking a few pots. Nothing is worse than hours of work wasted by being impatient. To begin, I apply a few base layers of terra sigillata using a sponge (1). Next, I create resist patterns on the surface using cut strips of newspaper that are dipped in water then adhered onto the pot. Be careful and adhere the paper well, or else the terra sigillata will bleed underneath and the resulting line or shape on the pot will not be crisp. I apply the terra sigillata with a sponge and blotting method as well as using a brush for some areas (2). Each color takes three to four coats, depending on the desired look and the clay body used. I use plastic 1-quart jars for all my colored terra sigillata, with the colors written on the top of the jar. Sometimes I wax over the terra-sigillata shape I just made, then remove the resist paper so I can apply other colors adjoining that one without having to use a brush. 

After the bisque firing, I apply a black wash to every piece with a mixture of black underglaze and water, which is not a very scientific or measured ratio: I simply pour a few tablespoons of black Amaco Velvet underglaze into a 1-quart jar along with some water and shake it. After applying the black wash (3), I wipe each piece with a wet sponge, leaving a light layer of black over the whole piece, which gives the surface some depth when the black sits in the marks made during the forming process (4). It also gives the piece a patina that suggests use and age. 

Sometimes after that, I apply automotive pinstriping tape to the surface and create fine lines that I fill with underglaze (5). I remove the tape prior to firing and refine the shapes with a knife (6). I glaze the interior with a liner glaze called Cream, which I buy premixed from Clayscapes Pottery in Syracuse, New York. I sign all my pieces on the bottom with black underglaze, and then the final step is my signature X that I put on each piece. Sometimes I hide it, and other times I put it on the part of a pot I want to accentuate. My thought behind the X is this: they say X marks the spot, so if you’re holding one of my pieces, you’re exactly where you need to be. 

the author Mike Griffin is originally from Long Island, but moved to the Finger Lakes region in New York. He found his love for clay while living in the Alfred area. As a golf professional in the summer, he only makes pots in the winter, when his course is closed. Griffin is looking to expand as an artist and to become a full time potter when he retires. To learn more, follow him on Instagram: @mike_griffin_ceramics.