ceramics and pottery processes and techniques of production by frank atuhairwe

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CERAMICS AND POTTERY PROCESSES AND TECHNIQUES OF PRODUCTION By Frank Atuhairwe

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CERAMICS AND POTTERY

PROCESSES AND TECHNIQUES OF PRODUCTION

By Frank Atuhairwe

TERMS USED

Bisque ware= A fired/ baked piece

green ware = an unfired piece

CERAMICS AND POTTERY

• Ceramics is the Art of making and decorating earthen or other functional and decorative wares by using clay, glass, porcelain, plastic as the raw materials.

• The most common and available material in the school situation is clay. Therefore to make any ceramics, one has to first understand clay, its properties or characteristics, clay preparation.

• The latter stage will be to learn the techniques of building ceramic wares and finally the decoration techniques.

Ceramic wares

CLAY

Definition

• It’s a heavy earth or type of soil commonly found in marshland and is elastic when wet and hard when fired/ baked and is used to produce items like wall bricks, tiles, pots and kitchen wares

CHARACTERISTICS / PROPERTIES OF CLAY

• 1. Plasticity:

This is the ability of clay to hold any shape to which it is molded without breaking.

• 2. porosity:

The ability of clay to hold water

• 3. Shrinkage:

The ability or quality of reducing in size especially when drying up.

• 4. Vitrification

This is the quality of being converted to a glassy (vitreous) state during firing to

Become very hard.

CLAY PREPARATION

Clay preparation involves several steps as registered below:

1. Mining clay from its source like swamps with all impurities and or foreign bodies

like rock, roots, metal, e.t.c.2. Slaking; involves soaking in water, to break

down the large boulders to create a viscouse clay called Slip.

3. Sieving; clay slip is sieved to become very fine and eliminate gritt.

Clay preparation

4. Mixing; the slip is mixed by stiring as grogg (fired clay powder) and kept for 4days to mature

5. Drying; Spread the slip on clean flat area like floor to lose excess water content/ moisture to a leather-hard state( less sticky).

6. Kneading; to cause uniformity of the clay and to eliminate any air bubbles and small stones.

Clay preparation

7. Wedging; to check the uniformity of the leather-hard clay by cutting through it with thread.

8.Storage; in polythene bags, airtight containers like buckets or protected pits to retain moisture.

9. Usage; the clay is ready for making ceramic wares.

TECHNIQUES OF BUILDING CERAMICS

• PINCHING AND PULLING

A ball of clay is opened by the hand thumbs as the fingers pull up the walls gently to the required height and shape.

COIL METHOD Long cylindrical ropes/strings of clay are rolled or made and placed onto each other systematically while joining takes place on both the interior and exterior or only the interior.

• SLAB METHOD

a lump of clay is rolled into a wide sheet of about 1cm or more thickness.

measured slabs are cut out and joined together to a required style and shape of a ceramic ware.

Techniques continued• SCOOPING A lump of clay is made into a very

admirable shape or design, which is dissected into two halves then clay scooped out with a tool like a spoon from the halves leaving a uniform thickness of the walls. The two open halves are then joined together by scorring to form a beautiful ceramic ware.

Throwing

This is the making of ceramics wares by use of a potters wheel.

The wheel can be manual or electric.

Steps in throwing

Molding/casting

• A mold is an already made, manufactured, or constructed ware that is used in creation of other items by using its shape.

• A piece of work is made by building and pressing clay against the mold to reproduce its very shape. It is closely related to casting but the latter happens with hot material and the former with cold.

• A metal cup or dish can be a muold

DECORATION TECHNIQUES

1. COIL DÉCOR : this happens when small size coils are systematically or randomly pasted on the finished vase.

2. SPRIGGING: small pieces of clay are designed from the clay and also pasted on the leather hard vase

Coil decoration

Incision decorationINCISION: The use of

very sharp tools like a knife gouges to cut out some clay from the surface.

Décor continued

4. GLAZING: the application of a suspension on a pot then later fired to become glassy.

Sprig decoration

1. SPRIGGING: small pieces of clay are designed from the clay and also pasted on the leather hard vase

5. SLIP TRAILING: coloured slip is oozed onto the surface of a pot by use of gargets like syringes while creating patterns.

Impressed/ stamped decor

6. IMPRESSING/ STAMPING: A designed pattern on small tools like wood, rubber, linoleum, metal, e t c in pressed onto a leather- hard ware leaving beautiful impressions.

Décor continued

• BURNISHING:

This involves polishing the ceramics ware until it is very smooth and shiny.

FIRING CERAMICS

• Is the process of heating or baking green ware ceramics to very high temperatures for the to attain bisque state. The bisque ware turns to brick red color.

Meanwhile, glazed work turns glassy and brittle.

• Firing is done in several ways; in the open, closed firing in electric,firewood and oil kilns.

Electric kilns

CONCLUSION

Ceramics/ pottery can be very interesting especially when one develops the best attitude without looking at the dirty side of soil –the clay. It is so interesting that; some individuals snare at pottery in its raw state but are the best choosers of what they would like, actually WANT to take as a gift from the potter.

Enjoy clay like God enjoyed the creation of Man.

By frank Atuhairwe