How Japanese Pottery Is Shaped: Five Forming Methods

The same clay and the same glaze still give different forms depending on the maker's character and on the technique used to shape the clay. That is one of the things that makes Japanese ceramics interesting.

A bowl thrown on the wheel is startlingly thin and even, and running a finger inside it you find smooth concentric rings. A bowl formed by hand — tebineri — varies in thickness from place to place, its rim waves slightly, and it settles into the palm as if it were clinging there. Neither is superior. When the method of making changes, the character the piece gives off changes with it.

Our previous article on glazes covered what decides color. This one is about form. Once you can tell how a shape came into being when you pick a piece up, the way you choose changes.

This article follows the full sequence by which clay becomes pottery, then introduces five forming techniques, and finally explains how to choose pottery by the technique used to shape it.

How glaze changes the expression of a piece is covered in the article below, so please do take a look.

• Japanese Pottery Glazes: The Main Types Explained

From clay to finished pottery

Before getting into forming techniques, it helps to see the whole picture of making. Forming is only one scene in a long sequence.

1. Digging the clay

Everything begins with clay. Its properties differ completely from region to region, and that decides the character of the piece. Shigaraki clay is coarse and holds feldspar grains; Arita clay is white and dense, made by crushing porcelain stone. Clay can be carried anywhere, but there are qualities only the ground of a particular place can give.

2. Kneading the clay

Clay cannot be used as dug. Stones and impurities are removed, it is slaked in water and strained, then rested to develop plasticity. After that comes kneading in two stages.

• Ara-neri　The first kneading, which removes the large air pockets and evens out the stiffness.
• Kiku-neri　The finishing kneading. Pushing the clay while turning it produces a spiral like chrysanthemum petals, which is where the name comes from. It exists to drive out every remaining air pocket; neglect it and the pockets expand during firing and the piece cracks.

Three years for kiku-neri, ten for the wheel — that is how much mastery this unglamorous stage demands.

3. Shaping

This is our subject. Thrown on the wheel, formed by hand, coiled, built from slabs, cast in a mould. We look at each in detail in the second half of this article.

4. Trimming and decorating

The formed piece is dried to leather-hard, the foot ring (kodai) is trimmed out, and the thickness is evened across the whole. Carved decoration such as faceting (mentori) or fluting (shinogi) may also be applied at this stage. Trimming is sculpture by subtraction rather than addition, and it is here that the weight and feel of the piece are settled.

hakeme, chatter-marked tobikanna, and the slip ground for kohiki also happen at this stage.

5. Drying

The piece is dried completely. Rushing causes warping and cracks, so the potter takes time, watching the season and the weather.

6. Bisque firing

A low firing at around 800°C turns the piece into a porous bisque body. Going through bisque firing makes it easier to handle and readier to take glaze.

7. Underglaze painting

Designs are painted onto the bisque piece. The indigo patterning in cobalt of sometsuke belongs here. Because it goes beneath the glaze it is called underglaze painting.

8. Glazing

Dipped, poured, or sprayed. For detail, see our article on glaze.

9. The final firing

Fired to 1,200–1,300°C. Here the glaze vitrifies and the clay body tightens. It is the moment the piece takes its final form, and the air in the kiln — oxidation or reduction — together with the temperature decides the color.

10. Overglaze painting

Designs in red, gold, green and other colors are painted onto the fired piece and fixed at around 800°C. akae and the polychrome of Kutani belong here. Because overglaze painting sits on top of the glaze, a fingertip can feel a slight relief.

11. Finished

All of that takes a few weeks at the fastest, and months for a wood-fired piece. This is how many stages one piece passes through before it exists.

Five forming techniques

Now to the main subject. The ways of making the form of a piece divide broadly into five. Each gives the piece a different expression, and the strength and particular skill of the maker's hands then shift that expression further still.

Tebineri: the oldest and the freest

tebineri is forming clay with the hands alone, using no tools. A thumb is pushed into a lump of clay to open a hole, and the walls are raised by pinching between the fingers. It is how humanity first made pottery, and it remains the freest method.

A hand-built piece is never even in thickness. The rim waves and the cross-section never quite closes into a circle. But that is precisely the value of hand-building — the opposite pole from the evenness of the wheel, the trace of a human hand turned directly into form.

Tea bowls of Raku ware are made this way. The wheel would be faster and more accurate, and yet the clay is deliberately built by hand. What Sen no Rikyu sought was not a perfect circle but a form made to be held. Pick up a Raku bowl and it settles into the hollow of the palm with startling naturalness. That is not chance; it was made inside a palm.

Coiling: building by stacking

Coiling rolls clay into long ropes and stacks them in a spiral to build the walls of a piece. The stacked coils are smoothed and joined with fingers or a rib, and the inside and outside are evened out.

Its greatest advantage is sizes and shapes the wheel cannot produce. Large jars, big storage pots, asymmetrical flower containers. The wheel gives only circles, but coiling is free to be oval or angular. Jomon earthenware, and the great jars of Six Ancient Kilns, were made this way.

Smoothed carefully, the coil marks disappear; but some makers deliberately leave the ridges. It is a way of treating the visible record of the stacking itself as scenery on the surface.

Tatara-zukuri: assembled from slabs

tatara-zukuri cuts clay into slabs of even thickness — tatara — and assembles them into a form. Cutting, bending, joining: it is closer to woodwork or paper craft.

It produces flat planes, straight lines and corners the wheel could never make. Square plates, long plates, square bowls, flower containers with clearly defined faces. Slab-built pieces have definite edges to their outline, and food placed on them gains a tighter composition.

Bend a slab over a mould and gentle curves are possible too. Because even thickness is a precondition, shrinkage during drying is straightforward, and even large flat plates are less prone to warping — a practical advantage.

Slip casting: poured into a mould

Slip casting pours liquid clay, called slip, into a plaster mould. As the plaster draws off water, a layer of clay forms against the inner wall. At the right moment the excess slip is poured out and the remaining layer becomes the piece.

Its greatest advantage is producing the same form accurately, many times over. Complex shapes such as handles and spouts can be reproduced as long as a mould exists. In regions making everyday pottery such as Hasami ware, this technique plays a large role.

"Made in a mould equals mechanical and low in value" is a common assumption, and it is not accurate. Making the mould is itself advanced form-making: designing the master model, calculating shrinkage, planning how the mould divides — every part of it carries a craftsperson's judgement. And above all, uniform thinness and lightness are territory only casting can reach.

Wheel throwing: evenness made by rotation

the potter's wheel uses centrifugal force on a turning disc to lift the clay into a form. It is the most widely used method in Japan and the emblematic image of pottery making.

There are two kinds of wheel. The electric wheel is turned by a motor. The kick wheel is turned by the foot; its speed is not constant, and that fluctuation appears in the piece.

The mark of a thrown piece is the concentric ridges left inside, called rokurome. Run a finger along them and the speed and pressure with which the maker lifted the clay come straight to your fingertip. Stroke the inside of a piece you have bought. If there is a spiral, that is proof it was thrown.

The wheel can make thin, light, evenly balanced forms, but it cannot escape the circle. Oval or angular shapes have to be altered after throwing, or handed over to another technique.

Choosing pottery by forming technique

The point is not to memorise the names of techniques. The point is to become able to choose pottery that suits your own life. Three angles help.

1. Choose by use

2. Choose by how it feels in the hand

This is something to confirm by actually touching. Even among bowls, the feel in the hand differs completely with the forming technique.

On a thrown piece, the finger moves smoothly. You feel the concentric ridges, but nothing catches. Lightness and evenness are the source of the comfort.

On a hand-built piece, the finger stops. Differences in thickness, slight unevenness, asymmetry. The hand holds it while searching out the form, and you are that much more conscious of the piece. For a cup used every morning the wheel is easier, but for a bowl you drink tea from slowly on a day off, the catch of hand-building becomes richness.

On a slab-built piece, the edge of the rim meets the finger. A definite outline becomes, directly, a tactile sensation.

3. Choose by what you want to value

Last, and perhaps this is the heart of it.

• If you want a one-of-a-kind piece: hand building or coiling　No two are ever the same. The state of the maker's hands on the day of making shows directly in the form.
• If you want to trust it as a tool: the wheel or casting　Even, easy to handle, and if one chips there is a chance of getting the same again. Pottery that supports daily life needs that stability.

And here is what matters most: which technique was chosen is a statement of what the maker wanted from that piece. There are makers who can throw and deliberately build by hand. There are makers who could make a mould and instead throw one at a time. When you can see the reason behind that choice, a piece stops being merchandise and becomes that person's judgement.

So when you choose pottery, try asking this. Why did this person choose to make it this way?

How to tell the forming technique

Finally, some practical points for telling how a piece in your hands was made.

• Concentric ridges inside　Wheel throwing. Run a finger along and you feel the spiral.
• Thickness varying from place to place, a waving rim　Hand building. Often the cross-section is not a complete circle either.
• Joins or ridges running horizontally　Coiling. Visible when the coils were not smoothed all the way out.
• Corners, wide flat planes, an appealingly straight rim　Usually slab building.
• A join running vertically, extreme evenness and lightness, several identical forms　You can take it that slip casting produced the uniformity. The seam where the mould halves met sometimes remains as a vertical line.

Choose a piece while picturing its glaze and its making

Nokaze carries pottery from makers who throw, makers who build by hand, makers who assemble from slabs — pieces that keep the trace of each maker's hands. For every one of them, you know the maker's name and the maker's own words.

Which way of making suits your hands? Begin simply by looking.

Related guides

• Japanese Pottery Glazes: The Main Types Explained
• Keshiki: How to Read the 'Landscape' on a Pot

Pieces available at Nokaze

• Shinogi | Japanese Pottery with Hand-Carved Ridges
• Japanese Plates | Handmade Ceramic Plates from Japan