CHALICE ARTS UK LTD POTTERY HANDBOOK FOR PRIMARY SCHOOLS STEPHEN BRUCE 1 © Copyright Chalice Arts UK Limited www.chaliceartsuk.co.uk 2015 CONTENTS INTROUCTION MATERIALS AND TOOLS BISCUIT AND GLAZE FIRING PINCH POTS COILING SLAB BUILDINGS SIMPLE MOULDS MODELLING AND JEWELLERY TECHNIQUES FOR DECORATING CLAY HEALTH AND SAFETY GLOSSARY OF TERMS APPENDIX: Science Work Ideas for Pottery Projects with Children 2 INTRODUCTION Clay is a wonderful natural resource. It can be found in many parts of the world and therefore many cultures have developed rich traditions of pottery making. Clay is a readily accessible medium for all ages of primary school children to work with. Children engage and enjoy its properties, being able to push their fingers into it, to shape, squeeze and mould it, to join, model and build with it. To produce pottery work a kiln is desirable so that work can be fired and glazed. However, there are self-hardening clays available which provide a good substitute to natural clay and harden without firing. Schools without a kiln might approach a local secondary school to see if they would be prepared to fire their work or a company like Chalice Arts UK who offer a local firing service. This booklet is designed to introduce the main techniques of working with clay which can be developed with children of primary age. Co-ordinators – understanding this paragraph is vital to raising standards of art – ensuring continuity and progression. Using clay can contribute to both Art and Technology within the National Curriculum. The use of clay can be supported with design drawings or other pieces of artwork which lead on to working with clay. Alternatively, the clay work children produce might lead to other imaginative work in painting for example. In this way the clay experience is not isolated and a “one off” lesson but can become part of a scheme of work which address continuity and progression. The development of projects using clay as a medium should also include work which contributes to knowledge and understanding of art. This might be done by looking at the work of adult potters and pottery from a variety of cultural traditions. It is also important to remember that other works of art such as paintings might form the stimulus for ceramic work. For example, a bowl project might be decorated with designs, colours, textures influenced by the study of a painting by the artist Klimt. Clay can also be studied as a material in science lessons and I have included an example of this in the appendix. The study of pieces of pottery from different cultures can also make an important contribution to developing knowledge and understanding of art. There are plenty of examples of work which depict stories and events which might contribute to areas of the curriculum like English and History. Ceramic work can provide inspiration for colour, its subject matter or textures and patterns. It is important to remember that just as with drawing there are developmental stages that children pass through as they mature and become more experienced with the use of clay. Clay activities should form a regular part of the art curriculum and should not be a once a year activity. We would expect children to produce more than one painting in the course of the year, the same is also the case with clay work. Children need regular experience with clay. In the early years children will model and mould clay, producing figures and animal forms with great delight. Even very young children are capable of producing small bowls and dishes which become more sophisticated as they mature and more advanced forms of decoration can be introduced. Progression needs to be considered carefully so that work in EYFS is not being duplicated in Y6 without there being clear progression and sophistication in techniques, forms and surface decoration. 3 MATERIALS AND TOOLS The most important material is clay and there are a wide variety of different clays available each having slightly different properties. The two main types used in schools are listed below. EARTHWARE CLAYS These are usually red or brown in colour and fire between 7000C and 11500C. The fired clay is porous and any pot made from this type of clay would need to be glazed if it were to be made waterproof. The characteristic colour is caused by impurities in the clay, mainly that of Iron Oxide. It is generally referred to as red clay. Red earthenware clay – a good clay for use in primary schools. Alternatively grey clay can be fired to earthenware temperatures or to higher temperatures and is equally suitable for use in primary schools STONEWARE CLAYS Stoneware clays are usually grey in colour and fire to higher temperatures between 12000C and 13000C. If fired to higher temperatures this clay produces a dense stone like appearance after firing and is non- porous. Stoneware clay or grey clay can be fired to earthenware temperatures but like red clay will need to be glazed to make it waterproof. Both red and grey clay are the two common types of clay used in schools. Grey stoneware clay (can also be fired to earthenware temperatures e.g. 1060 degrees Centigrade) 4 SLIP Slip is a liquid clay. It can be made by adding dry powdered clay to water and mixing using an electric food mixer. It should then be passed through a fine sieve or lawn. (It can be purchased ready mixed). Slip is used for making casts from plaster moulds, joining pieces of clay together and for decorating clay work. As a decorative medium it is particularly useful. Slip can be made in a variety of different colours by adding oxides to the slip. Alternatively, a range of coloured slips are commercially produced. Slip can be painted onto the surface of leather hard clay or it can be applied using a slip trailer. Slip – consistency of single or double cream and a slip trailer (like icing a cake) PREPARATION OF CLAY Clay suitable for working needs to be plastic (soft) and free from air bubbles. Clay can be used straight from a new clay bag but clay that is being re-used should be wedged and kneaded. Wedging clay is a process of folding the clay and slapping it down on the table top and then cutting it through with a wire cutter or nylon thread. The process is then repeated several times to expel air. Following the wedging process the clay should be kneaded. Use small, manageable pieces and gently push the heels of your hands into the clay and fold it over, repeat the process several times. Again, this helps to expel air and create an even workable clay. Wedging clay – this is a kneading technique to ensure even consistency TOOLS There are a range of modelling tools available and these are shown in the photograph below. A collection of textured items such as shells, stones, screws, keys, forks and pine cones should also be collected. These are very useful for creating pattern and texture on the surface of pieces of clay work. 5 Wooden or plastic modelling tools KILNS A kiln is an essential piece of equipment for firing ceramic work. Small electric kilns are available and these are ideal for primary schools. Top loading and front loading electric kilns. A small top loading kiln is idea for primary schools. BISCUIT AND GLAZE FIRING We fire clay to make it permanent. Firing produces a chemical change in the clay which is irreversible. Biscuit firing requires the clay to be heated slowly to a temperature in excess of 7000C. This drives off free water and chemically bound water in the clay. Clay changes into pottery or ceramic. BISCUIT FIRING The clay work should be bone dry before loading the kiln. Biscuit work can touch each other and can be stacked but care should be taken not to wedge work together as it will shrink during the firing and could cause damage. The temperature should be increased by 1000C per hour approximately. Once the work is red hot (about 7000C) the temperature can be raised more quickly. Most modern kilns have a temperature control built in and the firing process is very straight forward. Biscuit fired pottery can be finished by painting it with ordinary school water based paint or acrylic paints. It can also be given a coat of varnish is desired. The biscuit firing will have made the work strong and permanently hard. The alternative is to finish the work by glazing it and then firing the glazed pottery for a second time (glaze firing). For much primary school pottery a single biscuit firing is sufficient with painting techniques employed to finish off the work. 6 GLAZE FIRING The purpose of glazing is firstly to provide a strong non-porous finish and secondly to decorate your piece of pottery. Glazes can be purchased ready mixed or you can make up your own from powder or you can create coloured glazes by following simple recipes. Glazes are a science in themselves and can be very complex in preparation but clear glazes are easily mixed with water and ready mixed glazes can be purchased. Once you have your glaze prepared it can be applied to the pottery either with a brush, dipping the whole piece into a bucket of glaze or by pouring. The bottom of the piece must be completely wiped clean of glaze using a wet sponge to ensure that it does not stick to the kiln shelf during the firing as the glaze melts. Each piece is usually lifted off the kiln shelf using a small support called a stilt.