CRAFTSMANSHIP

The manufacturing process begins with the porcelain mass. This consists of about half kaolin (china clay) and a quarter each of feldspar and quartz. The purity of the raw materials guarantees the desired top quality and the exact recipe is a well-kept secret, the so-called arcanum. Kaolin, feldspar and quartz are first mixed with water and sieved so that all impurities are removed. The water is then pressed out of the liquid raw porcelain mass under great pressure. This creates large squares of kneadable material – the so-called filter cake – which are stored in damp cellars at almost one hundred percent humidity for several weeks.

Based on a freehand drawing, the modeling person creates an initial plaster model on a 1:1 scale. A second model, which is approximately 16 percent larger, is required to compensate for the loss of volume during drying and firing. A multi-part working mold is then built around the model. For complex figures, more than 80 individual parts can be created.

Objects such as pots, figures or other fine molds are usually cast. To do this, the filter cakes have to be liquefied again so that the raw mass meets the precisely defined properties so that it can later be slowly poured into the rotating working molds made of plaster. As plaster attracts water, an increasingly hardening layer forms on the mold walls. As soon as the desired thickness is reached, the remaining, still liquid mass is poured out of the mold. The casting then dries and can be released.

If the porcelain is not to be cast, but shaped and turned as with most Plates and bowls, the porcelain mass must have a firmer consistency. For this purpose, the filter cake is vented and compressed into a cylindrical hump. It takes a lot of fingertip feeling to achieve exactly the required moisture content of the mass. Unlike pottery, the blank is not freely formed on the turntable, but turned into or onto a special rotating product hollow form.

The individual parts produced by casting or turning are assembled (garnished) with a paste-like porcelain mass, the so-called slip. A coffee pot , for example, consists of a body, spout, handle, lid and knob. When garnishing, it is important to work quickly so that the parts do not dry out. Seams are neatly plastered. Finally, the finished product is worked over again with brushes and sponges so that any irregularities disappear.

As long as the blank is still damp, the porcelain can be cut. This work requires a high degree of skill and patience. Around 3,000 cuts have to be made precisely by hand for the openwork edge of the SCHINKELKORB alone.