The Encyclopedia of Pottery Techniques: A Unique Visual Directory of Pottery Techniques, with Guidance on How to Use Them

By Peter Cosentino

The new and updated edition. “Nicely illustrated . . . provides how-to information and photos on a variety of making and decorating techniques.” —Ceramics Monthly

Inside, discover all the major pottery techniques used the world over, from time-honoured traditional methods to exciting new developments. These include coiling, combing, resist decoration, sgraffito, slabbing and texturing clay. Once you’ve learnt these essential techniques, put your new skills into practice with a wealth of inspirational examples, ranging from bowls, vases and cups, to plaques, spheres and sculpture.

In addition, advice on materials and equipment is provided to help you on your crafting journey, including kilns, glazes, moulds and more. Finally, a gallery of stunning images is featured throughout the book, demonstrating an array of beautiful designs by established potters and ceramicists that will inspire both beginner and experienced potters.

“The book’s subtitle says it well.” —CreativeCrafter.com

• Language: English
• Publisher: Open Road Integrated Media
• Release date: Sep 27, 2018
• ISBN: 9781781266069

Book preview

Techniques

When a piece of pottery appeals to us the technicalities of type of clay used, style of decoration or firing temperature seem of secondary importance; it is only when we analyse why we like or dislike an object that we begin to look more deeply at the techniques and processes involved in the journey from raw clay to kiln. But the spirit’ of good pottery is no mere accident; it is the result of a harmonious bonding of the elements of design and technique through the knowledge and creativity of the potter.

Even the most abstract piece of pottery requires technical understanding. A piece may look so simple that one feels anyone with or without pottery experience could have made it, but in fact the potter was only able to achieve what they wanted through having a good grasp of certain important techniques.

Ideas are often sparked off by an investigation into technique and process, since these provide a basic framework for personal creativity. The aim in this first part of the book is to provide such a framework, with a comprehensive range of techniques represented. Using step-by-step demonstrations and finished examples the book shows how to tackle the forming methods of pinching, slabbing and throwing, and explains ways of decoration. The cross-referencing system will point you in the right direction if you need to know a little about one technique before you can tackle another.

I hope you will find this section useful and want to experiment with some or all of the techniques yourself. Although here each technique has been illustrated separately in the interests of clarity, this isolation of technique is far from desirable in practice. In reality, one technique merges with another, and most pieces of work will encompass several techniques in both construction and decoration, a fact clearly apparent in the wide range of potters’ work shown throughout the book.

Hand Tools

It is not necessary to spend a lot of money on tools, as a few basics will suffice to begin with. One throwing rib, one sponge, a wire and a ribbon tool are all you need initially. Many pottery tools can be made at home, which is not only inexpensive but also rewarding because you can make the exact shape that you require.

Illustrated here are the most commonly used tools for hand building and throwing. As you gain experience you will discover which are the best tools for you and the job in hand. Every potter has their own toolkit, containing a mix of handmade, modified or shop-bought tools.

Craft knife

A craft knife is always useful to have to hand and can be used to trim clay or to cut decoration.

Hole cutter

These are used to cut circular holes in leather-hard clay, such as strainer holes in teapots.

Kidneys

Kidneys can be used to either smooth the surface of wet pots or to remove clay during turning when the pot is leather-hard. They are always made from metal, but come in different shapes and thicknesses.

Sponges

Natural or man-made sponges are used to remove water from pots, to smooth rims and to clean surfaces. Most potters have a selection of sponges.

Bamboo tools

These are used for sealing joins in pots and for creating different surface textures. They can also be used to model clay.

Callipers

These are most often used for measuring the width of lids and galleries. They can be set to a particular width and put aside until needed later.

Paint scraper

A household paint scraper is a useful tool for cleaning benches and boards. It can also be used to remove wooden bats from the wheel, clean the wheel head quickly, shape wet clay and to create a bevel under a wet pot.

Ribbon tools

These are so called because they remove ribbons of clay from leather-hard pots during turning. They are metal loops on a wooden handle and come in many different shapes.

Wire

A wire is used to cut through clay, either during wedging or when removing pots from the wheel. The wire can be metal or plastic, but should have wooden toggles on either end to grip.

Throwing ribs

Throwing ribs can be made from wood, metal or plastic. You can make your own from old credit cards or buy wooden ones from suppliers. They are used for smoothing and shaping pots on the wheel.

Studio Equipment

Studio equipment is obviously more expensive than hand tools, but there are a number of items that are essential. All potters need a kiln, and those who wish to throw pottery will need a wheel. Whether you need other studio equipment will largely depend on the amount of work you intend to produce, but don’t buy expensive items until you are sure you will use them.

Momentum wheels

Momentum throwing wheels usually have a large, heavy flywheel powered directly by the feet or rotated using a stick placed in a notch on the wheel head.

Kick wheels

These throwing wheels are made of wood or metal, usually propelled by a pedal or crank shaft operated by the potter’s foot spinning a flywheel.

Electric wheels

These come in a variety of sizes. Some are large with integrated seats, and others small and adjustable in height, with remote foot pedals.

Banding wheels

Banding wheels are used when coiling, hand building and decorating. They come in different sizes and weights.

Kilns

Kilns are the most essential piece of equipment in a pottery studio. Electric kilns are obtainable in a range of sizes, from small mains-operated hobby kilns to large commercial ones. Gas kilns are useful if you wish to fire stoneware in reduction. Front-loading kilns are easier to pack, but top loaders are usually cheaper.

Spraying equipment

Spraying equipment is needed if you intend to spray glazes or colours, in which case a good-quality spray gun Í and compressor will be essential. Compressors come in various types, some with air reservoirs and some with only a direct feed to the gun.

Additives

Clay in its naturally found state is rarely ideal for use by the potter, so other materials are added to make it behave in the way required. It may, for example, be either too plastic or not plastic enough; its colour when fired might be too light, too dark, or simply unpleasant; it may not be able to withstand the temperature demanded of it during firing. All of these problems and numerous others can be solved by the addition of other ceramic materials, often no more complicated than the mixing of two or more different types of clay. Clay manufacturers and many individual potters mix clay bodies to their own particular recipes.

The addition of grog to clays (usually fired and ground fireclay obtainable in different grain sizes) and a whole variety of different-coloured sands are commonly used to minimise shrinkage, give extra strength to the clay and improve both its texture and its colour. Additives that alter the clay’s physical properties in this way are normally introduced during the preparation or manufacturing stage. Colouring stains can be used to give precise colours to a clay. Some potters introduce materials that react in a dramatic way. The addition of materials which will fuse, bleed or ooze out of the main clay body or glaze at temperatures below that required for the main body to mature can produce exciting effects, such as those seen in the work of potter Ewen Henderson.

Top, left to right: Porcelain, stoneware, red earthenware. Bottom, left to right: Raku, crank mix, smooth stoneware.

A variety of different clays can be obtained from pottery suppliers, a small selection of which is shown here. These are specially prepared, and can be reliably expected to behave in predictable ways during forming and consequent firings. Although the fired colour of most clays will be different from the pre-fired one, these will give an indication of the choices of colour and texture open to the potter.

Top, left to right: Sand, coarse grog. Bottom, left to right: Fine grog, red grog made from crushed brick.

Sands and grogs of varying coarseness can be used to add texture to clays or increase their strength and to some extent their colour. Some grogs, such as the crushed red brick shown here, will only tolerate temperatures of up to 1100°C (2012°F), after which they will melt and bleed through to the clay surface.

Where precise clay colours are required, colouring stains, or ‘body stains’, can be mixed into clays. These are bought in powdered form, and are available in both bold and subtle hues. Unless a dark-coloured clay is required, stains should be added to a white or light-coloured base clay.

To form interesting surface textures, combustible materials that will burn away during firing can be introduced to the clay, or pressed into the surface while the clay is still pliable.

Colouring

Colour in pottery is achieved by the use of various metal oxides. Clay stains or colourants derived from metal oxides can be mixed into the clay to alter its basic colour before use, common examples of this technique being Wedgwood’s blue and green jasperware and black basalt ware. Liquid clays with additions of oxides to form coloured slips or ‘engobes’ can either colour the whole surface by completely covering it or can be applied as a decorative effect (see Slip Decoration, page 77 and Glazing, page 90) prior to biscuit firing. In either case, glaze can be applied on top. Specially prepared underglaze colours or metal oxides can be painted or sprayed onto dry or biscuit pottery prior to glazing, when the colours achieve their full richness. Metal oxides or in-glaze colour derivatives can be introduced to a glaze to produce a particular colour once the glaze firing is complete, or alternately a piece of pottery can be painted or sprayed with oxides after glazing but before firing (see Drawing, page 89, and Majolica, page 84). Once pottery has been glaze fired, on-glaze colours or enamels can be applied to the surface and refired at a low temperature to set them.

Sandy Brown’s plate displays an artistic and expressionistic use of bold, often raw, colour. She uses a variety of metallic oxides and commercial stains to decorate the surface of her work to produce lively, uninhibited surfaces.

Colourants such as oxides and an almost infinite number of specially prepared glaze stains can be added to glazes to produce all-over colour. The strong yellow on this porcelain bowl by Lucie Rie was achieved by adding uranium oxide to the glaze.

Iron, copper, cobalt, manganese, chromium, nickel, vanadium, ilmenite and rutile are the most commonly used metal oxides from which most ceramic colours are derived.

Before press moulding the form, Jo Connell prepares a thick block of white clay, then bonds a paper-thin layer of a different clay, stained with copper oxide, on top. The surface can then be printed and scored using stamps and drawing tools. Firing to earthenware temperature ensures the vivid colour is retained.

Subtle, earthy colouring is an important element of the work of Michael Bayley, which reflects his love of the natural landscape. He achieves his range of colours – from creams to dark browns – by adding iron, manganese oxide and a variety of sands and grogs to his clay.

The combination of decorative methods, application of slips, oxides and colourants, underand over-glaze painting, and the overlaying and overlapping of many different-coloured glazes all contribute to the rich palette of colour which is a feature of the work of potter John Glick.

This raku-fired Heron and Carp Vase is by Frank Boyden, a potter who skilfully employs a combination of slips, glaze and firing technique to achieve the