Clay material processing is a process of preparing the raw material of clay into the clay body is ready to be used for manufacturing ceramic objects as materials or cast plastic (slip), clay processing can be done starting from the simple to the complex process.
Clay material processing as an early stage in the process of making ceramic objects can be performed with a variety of techniques, this is related to the type of clay material, the type of ceramic objects, forming techniques, and the availability of equipment.
Natural clay as a source of raw material for making ceramic objects found in various parts of Indonesia, but still rare natural clay materials (raw) can be used directly, to be used should always be through the clay treatment process.
Clay used to make ceramic objects must memenuhii certain requirements are: plastic, homogeneous, free of air bubbles and impurities. To meet these requirements, processing the mixture of various types of clay materials need to be done carefully, precisely and accurately, because the processing will affect the next process. Processing of clay are of two kinds, namely the technique of wet processing and dry techniques.
Various kinds of processing or preparation of clay into a ceramic body mass can be done, such as:
1. Preparing clay bodydari manually natural clay wet.
2. Preparing clay body of natural clay dried manually.
3. Preparing the clay body of natural clay masinal wet.
4. Preparation of prepared clay body masinal hard mineral wet.
5. Preparation of the clay body cast for print formation techniques.
Preparation of Clay Clay Natural Body Manual
The processing of natural clay material manually wet is the simplest process, because the material is processed a single clay materials, namely natural clay material that can be used directly to form ceramic objects without mixing it with other materials, such as clay and Earthenware stoneware. Manual processing of wet clay body is usually performed by traditional ceramic artisans with local materials available in the area.
Processing bodies wet clay manually performed through the following steps.
1. Drying
Jemurlah clay until it is completely dry. To speed up the drying process of the clay material, should not be too big chunks but small pieces so that the water in the clay out quickly and evenly on the entire surface of the clay, because in dry conditions holding capacity of clay particles is low.
Soak dried clay materials in the water to be easily destroyed. Hard clay that requires a long time to disintegrate, while the software will soon be destroyed after immersion. At this stage, experiencing slaking clay, clay expands and shattered men so small parts, making it slip.
3. Stirring
Stir-stir clay after clay soaked condition is completely destroyed, it will ease the process of mixing. Do it repeatedly to speed up the clay into homogeneous conditions such as mud clay (slip).
4. Filtering
Strain clay material in the form of the clay slurry using a 60 mesh sieve. Screening conducted soil clean of impurities such as: root, charcoal, gravel and so on. Place the clay on the results of screening buckets and allowed to enable the deposition of clay.
5. Precipitation
Do the deposition of clay slip for one to three days and the soil will settle at the top of the water would seem to be at the top. Subsequently Take the water on the land surface to the extent of siltation. The longer the deposition of the less water.
6. Thickening
Perform coagulation clay slip is a way to pour mud clay (slip) on the table casts, or burlap sack until the soil thickens. Coagulation is the process of evaporation of water content (dewatering) of silt clay (slip), this happens because the water is absorbed by the plaster and evaporation temperatures.
7. Pengulian
Do a soil material pengulian plastic clay plaster on the table. This meant that Pengulian obtaining clay really plastic and homogeneous. Form the clay plastic into a cylindrical shape or with heavy beams and certain size then insert in a plastic bag and tied tightly.
8. Ripening
Peramlah plastic clay has diuli in storage tub material covered in order humidity is maintained. Perform curing during less than 7 days, the longer stored the better after the clay is ready is used.
