Automotive modelling clay extruding machine - GIF

[hemmjo]

The clay used for sculpting models for artists and industry is plasticine modeling clay. There are various formulations using wax or various oils as binders rather than water. There is little or no shrinkage since the wax or oil does not evaporate.

It is correct that regular "potters clay" when kept at the correct moisture content can be reworked forever. It can also be reworked after it is completely dry. However the shrinkage of potters clay makes it unsuitable for the precision modeling industries require. The shrink rate is easily above 10%, depending on the beginning water content. Artists who sculpt in potters clay, for eventual firing, must use various methods to keep their project at a consistent moisture content as they work, to prevent shrinkage cracks. If necessary there are shrink rules, just like used in foundries, if finished size is critical.

The machine shown simply works the clay scraps back into a homogeneous mass, removing air and assuring consistency throughout the clay.