Coil Building
This page will go over some basic guideines for coil building and give you some ideas about how to use this building technique.
Coiling is the term for building ceramics out of coils or sausage shapes.
You should roll the coil on an absorbant board such as :
I also use a board for rolling and a smaller square board for building on. Because rolling the coils takes up a bit of room.
If you are working with students you can slip and scoring as joining techniques for coil pots. I tend to teach the technique without slip and scoring, using a moist clay. But if students work more slowly or have particularly warm hands, or it is a warm day, or they touch their pot too much, they will most likely have to use slip and scoring because their clay will become too dry to join.
scoring on a coil pot is best done with a thin potters knife.
Slip - can be made by mixing clay and water. It is more easily made by dropping completely dry clay peices into water.
The little jug above has been started off with a pinch pot. If you start with a pinch pot, you will have a rounded base. If you want a flat base for your coil pot, you need to make a slab base. The slab should be rolled out about 1 cm thick and cut to shape.
When joing coils without slip and scoring, I always blend the clay downwards on one side ( such as the inside) and upwards on the other side.
So I place the coils on the pot as a spiral, blending down on the insdie as I go around. When the coil has run out. I blend up on the outside, till I am happy with the shape of the pot.
Then I will add the next coil, continuing in the spiral.
If you work in a spiral it will make it easier to keep the shape of the pot how you want it.
decorative coiling
When you do decorative coiling work, you seal the coils on the inside but not on the outside.
In this method you can see the patterns of the coils.
It is really important to dry the decorative coil pots more slowly to enable the clay to meld.
If you dry the pots quickly they will be more inclined to crack between the coils.
right: open coiled jug with pressed decoration added, using a stamp and a skewer.
The feet were added last.
You can also do decorative coiling very easily in a mould.
Place your coils into the mould in a decorative manner, filling up all gaps with clay and then smooth the surface.
Adding colour to decorative coil projects.
Inlaid slip is also a good method to use, to add colour to the project and to bring out the decoration.
When the pot is hard enough to handle, you paint liquid underglaze or decorating slip into the the gaps between the coils.
You can do this quite roughly and quickly. Then you use a knife or a metal scoop tool to scrape back the slip from the top surface, so it is only left in the cracks. If you prefer a smoother look, you can use a damp sponge to wipe back. I personally prefer the scraping method as the edges have more definition. There is a clear edge between the colour and the natural clay.
You can also paint or sponge oxide into the cracks and wipe this off with a clean well wrung sponge.
below: a tile made in a mould. The back of the tile has been smoothed over so that the coils are well joined.
The two clays are terracotta and white earthenware handbuilding and have a similar shrink rate.
I often use them together in ceramic peices and they fire well. Not all clays can be joined so easily.
The tile has been popped out of the mould while soft so that it could be decorated with little marks. These were made with a skewer - my favourite decorating tool.
This page will go over some basic guideines for coil building and give you some ideas about how to use this building technique.
Coiling is the term for building ceramics out of coils or sausage shapes.
You should roll the coil on an absorbant board such as :
- as the rough side of masonite,
- unsealed mdf,
- particle board,
- cement sheet.
- plywood,
I also use a board for rolling and a smaller square board for building on. Because rolling the coils takes up a bit of room.
If you are working with students you can slip and scoring as joining techniques for coil pots. I tend to teach the technique without slip and scoring, using a moist clay. But if students work more slowly or have particularly warm hands, or it is a warm day, or they touch their pot too much, they will most likely have to use slip and scoring because their clay will become too dry to join.
scoring on a coil pot is best done with a thin potters knife.
Slip - can be made by mixing clay and water. It is more easily made by dropping completely dry clay peices into water.
The little jug above has been started off with a pinch pot. If you start with a pinch pot, you will have a rounded base. If you want a flat base for your coil pot, you need to make a slab base. The slab should be rolled out about 1 cm thick and cut to shape.
When joing coils without slip and scoring, I always blend the clay downwards on one side ( such as the inside) and upwards on the other side.
So I place the coils on the pot as a spiral, blending down on the insdie as I go around. When the coil has run out. I blend up on the outside, till I am happy with the shape of the pot.
Then I will add the next coil, continuing in the spiral.
If you work in a spiral it will make it easier to keep the shape of the pot how you want it.
decorative coiling
When you do decorative coiling work, you seal the coils on the inside but not on the outside.
In this method you can see the patterns of the coils.
It is really important to dry the decorative coil pots more slowly to enable the clay to meld.
If you dry the pots quickly they will be more inclined to crack between the coils.
right: open coiled jug with pressed decoration added, using a stamp and a skewer.
The feet were added last.
You can also do decorative coiling very easily in a mould.
Place your coils into the mould in a decorative manner, filling up all gaps with clay and then smooth the surface.
Adding colour to decorative coil projects.
Inlaid slip is also a good method to use, to add colour to the project and to bring out the decoration.
When the pot is hard enough to handle, you paint liquid underglaze or decorating slip into the the gaps between the coils.
You can do this quite roughly and quickly. Then you use a knife or a metal scoop tool to scrape back the slip from the top surface, so it is only left in the cracks. If you prefer a smoother look, you can use a damp sponge to wipe back. I personally prefer the scraping method as the edges have more definition. There is a clear edge between the colour and the natural clay.
You can also paint or sponge oxide into the cracks and wipe this off with a clean well wrung sponge.
below: a tile made in a mould. The back of the tile has been smoothed over so that the coils are well joined.
The two clays are terracotta and white earthenware handbuilding and have a similar shrink rate.
I often use them together in ceramic peices and they fire well. Not all clays can be joined so easily.
The tile has been popped out of the mould while soft so that it could be decorated with little marks. These were made with a skewer - my favourite decorating tool.
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