The Window Between Too Wet and Too Dry

Sgraffito is all about timing. Scratch too early and the slip smears and clogs the tool. Scratch too late and the dry slip powders and chips unpredictably. There is a narrow sweet spot, and learning to recognize it is the main skill.

The Right Stage

The coating should be:

• Dry to the touch: Your finger does not pick up color when you press lightly.
• Not yet powdery: When you scratch, curls or ribbons of slip peel away cleanly; they do not crumble or dust off.
• Still slightly cool: If the slip feels room temperature and powdery, you are past the sweet spot.

At this stage, a scratched line is clean and crisp, with sharp edges and no smearing.

Drawing Your Design

You can scratch freehand or transfer a design first:

• Freehand: Draw directly with the tool. Confident, fluid lines look best.
• Transfer: Draw your design on tracing paper. Tape it to the pot and poke through with a pin tool to transfer dots. Remove the paper and scratch between the dots.
• Pencil sketch: Sketch lightly on the slip surface with a soft pencil. The pencil marks burn away in the kiln.

Cleaning the Lines

After scratching, small burrs of lifted slip remain along the edges of the lines. You can:

• Blow them away gently.
• Use a soft brush to sweep them away.
• Leave them for a rougher, more organic look.

Do not use a damp tool or finger to clean; it will smear the slip into the scratched lines.

Pro Tip

Work under good directional light (raking light from the side). The shadows in your scratched lines show up clearly in raking light, letting you see the design as you build it.

Line Cleanup Flow

After carving pass:

• Dry brush loose burrs
• Inspect under raking light
• Recut weak lines once only

Overworking lines makes edges fuzzy and weakens clarity.

The Bigger Picture

Korean potters developed sgraffito-like techniques centuries ago as part of the buncheong tradition, where white slip was carved, stamped, and scratched to reveal the dark clay beneath. For more on how slip coatings and scratched decoration evolved together across cultures, the Wikipedia article on slipware provides a broad historical overview.