Make Casting Mold from Plaster Model (One Piece)

The main principle for making one piece mold is the shape must wider to the top. Otherwise impossible to release the model from the mold because will be stuck, even in little difference.

Another thing must be note is a kind of separator we used. I make separator by myself from white bath soap. The soap is cut into small pieces and cook with little water and coconut oil. The result is liquid mixture. This separator is good enough to me. To apply the separator on the model surface can use sponge like picture in the bottom. The process binding needs several times until has shiny surface.

To release model from the mold, you back mold and struck by hammer. But do not directly must be put the wood first (fig. 5). To hit the mold you must use shock technique, do not use full power. Before that you need put the props, so after hit several times the mold will go down by itself (fig. 6). 

1. Place the model on bat and a gap between model and bat cover with wet clay

2. The excess of clay trimmed neatly

3. Use separator

4. Pour plaster slip

5. To release the model struck the bottom by hammer (use props)

6. The model will release after struck several times

Trimming Plaster for Model

1. Make a base clay for model

2. Using fiber make a boundaries and tied

3. Pour the plaster into container

4. Ready for trimmming (cheese hard)

5. Trimming

6. Completly model

Usually model for casting is made of clay. The forming technique could be throwing, pinching, or coiling. As alternative, you can use ready made product like artificial bird, mug, or plastic glass. For long usage you can use plaster, meanwhile the clay model will damage for once used. Also the plaster model is useful in consistency of size if make for next molds. 

The standard procedure making model is using special equipment. But actually you can use kick wheel. The important is a right moment for trimming and kind of tools. The tools also do not need special ones, we can use simple tools like iron cutter, iron scraper or iron ruler. Trimming for plaster and clay is really different. You need more effort to trim plaster.   

To shape the plaster model you must have some tricks for satisfied result. The plaster don't let hard, but must in cheese hard to begin trimming. It must be in hurry because the plaster will be hard by time to time so that it will be more difficult for trimming.

Make a Bowl by Solid Casting

There is another technique in casting besides drain casting, it's called solid casting. As general drain casting is pouring the slip into the mold and when have certain thickness the remains poured back into container. While solid casting there is no remains, the slip is allowed to semi leather hard in the mold. Another characteristic is the drain casting for getting outer shape, meanwhile solid casting for getting outer and inner shape. Therefore the mold of solid casting could have a positive and negative shape.

Technically solid casting is more difficult. The bowl often stick to the mold. Usually before pour the slip, each mold is given talc powder evenly. Also the slip consistency must fluid enough. When the bowl start to separate to the mold, you can hit by hand the edge of mold for several times, until make a gap between bowl and mold.

The  results of solid casting are more constant (shape and thickness), because drying process more even (have two shape molds: positive and negative). But anyway, there is form limitation for the technique. The form must be simple and wider into the top, such as bowl or cone. The form like vases wide then tapers back can't be done by this technique, because it will be stuck when lifted from the mold. 

1. Pour the slip

2. Wait until the certain thickness

3. Pour the slip back

4. Keep the mold in first position

5. Lift the positive mold

6. Keep the bowl in negative mold

7. Wait until the bowl separate

Casting the Bottle

Many things could be causes unsatisfactory casting. Besides the technique problems also the batch of material either the slip or the plaster. The problems usually the clay stick to surface mold, the thickness takes very long time or cracks on body surface.

We have to different the composition of plaster and water each technique making a certain mold, for press molding, jiggering, jelloying or slip casting. The proportion of plaster and water for slip casting usually 110-130:100. If too much plaster to water the mold has low absorption to the slip, while too little the mold has high absorption but not practical. Because the mold will quick saturated, therefore used several times only.

Slip casting just suite for the high firing. May be the low firing could be, but not practical because not effective and efficient for production. As general the simple formula for slip casting: stoneware clay, ball clay and kaolin. For deflocculent agent, add water glass.

Simple formula:

- Stoneware clay: 60%

- Ball clay: 10%

- Kaolin: 30%

- Water glass: 0.4-0.8%

- Water: 40-50% of weight the clay.

To modified the formula above can add feldspar, quartz, talc or whiting (non plastic material). All can quicker the thickness of the piece.

1. Pour the slip

2. Pour the slip back

3. Put the mold 45 degree

4. Wait until separate to the mold

5. Release each part of mold

6. All released

7. Trim the sphere

8. Final result

Make a Large Bowl (Hand Wheel Technique)

2. Press the rim firmly

1. Put a large clay and make a hole

3. Use both hand to lift the clay

4. Wider the edge

5. Getting wider

6. To steady wider press firmly from the inside

8. Final result

7. Use the hand to make steady

The pictures of above to demonstrate the making of large bowl by hand wheel. Many technique for making a large bowl, depends on habit and practical of the maker. For this technique the clay must soft enough and doesn't need much water to make the pot. In Indonesia, the ceramic craftsmen usually use soft cloth to help lifting the clay in throwing, not sponge or bare hands.

The pictures was taken in traditional ceramic center at Jatiwangi, Jawa Barat, Indonesia. From Bandung it takes 2,5 hours by bus. Jatiwangi is well known of roof tile in Indonesia. The quality of strength is especially liked by most people. Recently the prestige of the roof tile loosed by artificial roof, because more practical and cheaper. I think Jatiwangi needs revolution or drastic orientation changes in paradigm. The clay not just for roof tile but they can be more valuable economically as well esthetic of form.

The Second Jakarta Contemporary Ceramic Biennale, 2012

The second Jakarta Contemporary Ceramic Biennale was held on December 21 - January 20 2012 at Museum of Ceramic and Nort Art Space, Jakarta, Indonesia. The participants are from many countries, totally 46 artists. 

The aim of the Jakarta Contemporary Ceramic Biennale II, through the theme "Crafting Identity, is to attempt to engage in discourse about identity. "Crafting" refers to the practise of creating works using one's craftmanship abilities. Here, "Crafting Identity" is intended to mean any craft practise exercised to create an "identity". 

In addition to identity issues regarding the forms and techniques of ceramics, the issues of identity within the curatorial of "Crafting Identity" can be specified further. Issues range from Identity and its connection with discourses of spirituality, discourses of body and gender, discourses of art and memory, the culture of consumption (consumer culture), it's relation to production in work culture, historical reference, postcolonial condition, diaspora experience, locally and globality; and urban/industrial experience.The description of above is the quote of curatorial statment of Sujud Dartanto (Exhibition Curator). For further information you can visit the blog jakartacontemporaryceramic.wordpress.com

Tok Yu Xiang, Singapore

Micheal J. Doolan, Australia

Antonio S. Sinaga, Indonesia

Natas Setiabudhi, Indonesia

Vipoo Srivilasa, Australia-Thailand

I Made Arya Palguna, Indonesia

Maman Rikin, America-Indonesia

 Esnur Fauziana, Indonesia

Maria Bosch Perich, Spain

Tour of Ceramic Village (Plered, West Java)

Menuju tempat pengolahan tanah liat

Seorang local guide sedang menerangkan proses pengolahan tanah liat

Tungku bak.

Seorang perajin sedang loading produknya menggunakan tungku bak

Kunjungan mahasiswa ke salah satu perajin di sana

Sudut sebuah workshop di Plered

Sudut sebuah workshop di Plered

Diskusi antara perajin dan staf pengajar dari Kriya keramik ITB

Recently, we visited to ceramic village at Plered, Purwakarta City, West Java province. We are as a group of college students kriya keramik of ITB (Bandung Institute of Technology). They were 16 students and accompany by 4 lectures. From Bandung to Plered it takes 1 hour and half by bus. This activity is one of the program to the students for introducing the method of traditional ceramic makers. They have a good craftmanship and sometimes find a way that was unthinkable by students. They were introduced the common technique and facilities in some places. Looking around the clay sources and learning how to produce the workable clay by simple machine. And then came to the production places saw the facilities like the kilns, simple press machine and tools, etc.  

Plered is well known as a community of decorative ceramic. The forming technique what they use are pinching, coiling, press molding and throwing. But the most popular technique is throwing. To fire the pot they use woods as a fuel. The kiln is very traditional, just used red bricks for the construction and at the bottom there are some fire pits to put the fuel. Five years ago they have supporting from the goverment for the kiln. They got some modern kilns, used ceramic fibre and stell construction, but the fuel still from the woods. They don't use the plate for stacking and the glaze for the color, so the wares just stacked each others. For the colors they use paint (thinner base). What the carpenter or car painter need for their works also done by decoration man in the ceramic village.  

In Plered threre are 3 regions that have different uniqueness for each,  i.e. decorative ceramic (Anjun village), traditional vessel (Lio village), and vase specialities (Gunung cupu village). They use earthenware clay and will be red when fired.The products besides for the local market, they usually export. The destination are the middle east, Europe and America. The products are decorative ceramic only and mostly  flower pot and vase.