Coil Pottery: How to Build Even, Crack-Free Walls

Coil building is one of the oldest ways to make a pot, and it still works. You roll ropes of clay, stack them in rings and blend them into a wall. There is no wheel, and you can make forms that are hard to throw: wide, asymmetrical or very tall.

The skill is not in the coils. It is in blending them well and keeping the wall steady as it grows.

Start with a solid base

Roll a slab about 8 mm (1/3 in) thick and cut a circle or oval. Score the edge, add slip, and place your first coil right on it. The base needs to be thick enough not to crack as it dries, and flat enough to sit steadily.

Roll even coils

Uneven coils make uneven walls.

Start from a short, fat sausage of clay and roll with your fingers spread, moving outward.
Aim for a diameter of about 1.5 to 2 cm (a little over half an inch) for a first project.
Keep the clay slightly soft and cover coils you are not using so they do not dry and crack.

Our practice drill on rolling even coils is a ten-minute way to build the habit.

Stack, score and blend

Lay the coil on the rim of the base, trimming the end at an angle so the join overlaps.
Score the top of the wall where the new coil will sit, and add a little slip.
Press the coil down gently, then blend it into the wall on the inside using your thumb or a wooden tool.
Blend the outside too, pulling clay up from the coil below and down from the one above.
Repeat, staggering the joins so they do not line up.

The blending is the whole job. If you can still see coil lines, the wall is weak at those seams. You can leave them as decoration on the outside, but they must be joined on the inside.

Control the shape

Move the wall slightly in or out with every coil, not all at once. A wide-bellied vase builds out slowly and then returns. Place each coil a little further from the center to flare, and a little closer to taper.

Let the pot firm up as you work. A tall wall of wet clay will slump under its own weight. Stop for a while when the lower rings feel soft, covering the rim with plastic, and continue once it stiffens. This is the same logic as the clay stages.

Smooth and refine

When the form is built, scrape the surface with a metal rib, then a soft rib, to compress the clay and remove marks. Compressing the wall closes tiny gaps and reduces the risk of cracking.

Common problems

Cracks at the joins. The coils were too dry, or they were not blended inside.
A wobbly wall. Coils were uneven, or the pot was moved too much while soft.
Slumping. Build more slowly and let the base firm up between layers.
S-shaped base cracks. The base was too thick, or dried unevenly. See why pottery cracks.

First projects

A small cylinder pot, 15 cm tall
A coil planter
A curved vase, about 20 cm
A lidded jar with a coiled gallery

Write down the coil size, number of rings and the drying time you used. Repeating a good form is much easier when you have the numbers, and a project log in Claybook is a good place to keep them.