Published Jul 17, 2023
Painting with underglaze on pottery can be done either during the greenware phase, or the bisque phase. Nikki Mizak chooses to do her underglaze painting on bisque fired clay and enjoys building up layers as you do in watercolor painting.
In today's post, an excerpt from the Pottery Making Illustrated archive, Nikki explains her process for painting bisque fired clay with underglaze. – Jennifer Poellot Harnetty, editor
Painting Bisque Fired Clay with Underglaze
While underglaze decoration can be done at the greenware or bisque stage, I paint when pots are bisqued. Because I like painting bisque fired clay, I hold my piece with a cotton knit cloth so I don’t transfer any oils from my hand onto the pot. To achieve depth, it’s important to overlap some areas while leaving other areas with fewer layers. This also blends translucent and opaque layers, which are revealed after firing.
Painting bisque fired clay is a lot like watercolor painting in the application and mapping out of color. Although underglazes come in a wide variety of colors, when working with them, don’t limit yourself to straight-out-of-the-bottle colors; you can mix them as needed to achieve your desired look.
I use Amaco underglazes, but mix Velvets, LUGs, and SMUGs interchangeably. If you’re using different brands, test and see how they mix. Use bottled/distilled water to thin underglaze when painting because you don’t always know what minerals are in tap water and how they could affect your fired painting. Work from more watered-down underglazes in the first layers to less watered-down underglazes in later layers so that the final layers are strong in pigment. Keep in mind the number of overall layers applied; depending on the amount of water added, you may have anywhere from 2–6 layers.Note: Do some testing to see which colors require more layers and which are strong enough with fewer applications. After you complete the initial line drawing with a small brush, work from larger to smaller brushes.
Painting Bisque Fired Clay in Layers
When starting, I apply a quick sketch with underglaze (if you aren’t comfortable freehanding, you can sketch with a pencil), then begin to paint (1). With each step, keep in mind the direction of your brushstrokes for two reasons: for style and because after firing, the layers will reappear and blend.
Next, lay down a thin wash of each color-blocked area to build your layers upon (2). Continue painting each layer, using less and less water and moving down in brush sizes and brushstrokes (3).
Near the end of the painting, begin to paint with your most concentrated pigments; this brings all the larger brush strokes together (4). Those last vibrant details make the painting pop and bring the overall image together (5, 6).
Glazing and Firing
Once the painting is completed, I brush on or dip the pots in a clear glaze and fire them to cone 6. When the underglaze fires, it brightens and reveals the rich layers I’ve carefully built up.
Check out this post in the archives for a tutorial on drawing on pottery!
**First published in 2018.