Kupu Keramik

Welcome bin wilujeng sumping di blog Kupu Keramik with Natas Setiabudhi
. Blog ini berisi curhat ataupun sharing teknis tentang keramik art dan craft
juga hal-hal lain berkaitan dengan keseharian penulis. Bila ada uneg2 mangga pamiarsa komentaran secara blak-blakan..any comment I will accept openly..


Natas Setiabudhi

Thursday, May 9, 2013

Make Casting Mold from Plaster Model (One Piece)

The main principle for making one piece mold is the shape must wider to the top, for instance a bowl shape. Minimal has straight line from bottom to top, like cylinder cup. If has curve line in some area, even slightly the model can not release from the mold. It will be stuck. 

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

Wednesday, May 8, 2013

Trimming Plaster for Model

1. Make a base clay for model
2. Using fiber make a boundaries and tied
3. Pour plaster slip
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.