The Bright Angle Blog

What is slipcasting?

There is a major gap in the design fields involvement with materials and production process. One crucial aspect of The Bright Angle is that we design or facilitate design for a specific process specific to that material. The method we use in our studio is called slipcasting, which is a technique using mold systems and liquid porcelain to produce ceramic objects.

Currently the process we are set up to do in our studio is slipcasting ceramics. For a long time the idea of slipcasting was polluted by its utilization in industrial techniques to mass produce items, which I think is largely due to a number of factors. One factor would be the uninvolved nature of production labor, where there is very little problem solving or cerebral involvement. Another factor is that the mass produced items seem so sterile because the manner in which they were produced and because the designers were typically uninvolved or removed from the production process. For example, you would not have a trained potter with years of experience designing cast ceramic objects.

Pulling an Alex Reid cup from the mold.

The first step to slipcasting is acknowledging that the object that you are designing will be made with a process where the liquid porcelain has to go in and out of a cavity. In your design considerations for a slipcast piece you will be expecting there to be seams where the mold is opened because order to remove the molded object after it is made you will have to disassemble the mold around the object.

The second step of the slipcasting process is to make the original model. Once the concept and design have been established, that concept will need to be translated into two dimensions. Primarily profiles of the piece will be established on paper and in the computer. Once you have the two dimensional profile or framework for the piece you can create the item three dimensionally by considering a number of items: how to capture a negative of that positive model and imagining the mold system.

Step three will be to make models by sculpting in clay, carving out of plaster, 3d printing, using computer aided modeling tools or using found objects.

Step four is to make a mold or mold system for the model, which is a complex and involved problem that entails figuring out how to make negative stamps to encase the model while leaving space for the liquid porcelain to be inserted. Then the mold will be set to dry.

Step five will be to fill the mold with liquid clay, or slip. The clay acts as a sponge for water, so the mold will suck the water from the clay. A skin forms on the interior face of the mold, and ultimately the longer you leave it in the mold the thicker it will become. You then will dump the excess clay back out of the mold, leaving the cast of the piece. Once it is dry, the mold will be disassembled a hollow model will be pulled from the mold. Positive from negative. Afterwards the cast piece will be cleaned up, dried, fired and glazed.

Pouring slip into a mold.

People know that buying from an artist is better than from walmart, but in terms of the item that they actually receive they often do not. A mug would be a simple example. It would be designed by a potter who has experience using a mug and has considered it. A smaller mug will have a one fingered handle, and it will make sense because you only need one finger to hold the liquid and its balanced visually. Potters will consider the foot of the mug and how it will sit on a table - our mugs will not scratch surfaces. Mugs will be considered where they are being used as well as where they are inactive. Consider the shape of the lip, if it is bent in it will hold heat better for comfort. These are things that only people will consider who are familiar with design material. Users should not have to consider, they should subliminally accept them which makes them appreciate the design and once they acknowledge and know that these design aspects are taken into consideration they will appreciate and respect the designer/maker more. Handufacturing, we don’t have conveyor belts or automated machines. We make molds to facilitate reproduction with high quality and consistency so that good design and objects are available to a wide number of people. That being said, they are still limited edition.