PLASTER WORKSHOP 1

CERAMICS & PLASTER

Creating Formwork and Plaster - 9th October 2017

Introduction

My first lesson on ceramics was about making plaster and applying it on various formwork and surfaces to create pieces of artwork. 

The formwork or moulds that can be used can be both solid and hollow and it can also be made of various materials. These materials include:

• wood
• paper
• cardboard
• gel
• rubber

The characteristics of the material that we choose for our formwork is essential to consider. for example, if the mould is made of an absorbent material, a release agent will need to be used on the surface. If the plaster is casted on wood, paper or cardboard moulds, vaseline is applied on the surface as a release agent. Plaster can also be casted on on a plaster formwork, and in this case a special solution is used as a release agent.

One of the advantages of using plaster is that it can create colored finishes. Color can be either mixed together with the plaster or color can be applied after the plaster is casted and hardened. 

Process of preparing plaster and applying it on a formwork. 

The first step is to select a formwork and check if it requires a release agent. At the workshop we used a wood formwork, so we applied Vaseline on the surfaces to prevent the plaster from absorbing into the formwork.

Then Ms Claire Wanton demonstrated how to create a plaster mix using plaster powder and water. She instructed on creating small mixes so even if something goes wrong a small potion is wasted. When creating a mix, first remove any watches or jewellery, wear gloves (if needed), and wear a mask for safety. Pour water into a mixing bowl and slowly pour plaster evenly throughout the water surface until the powder form small peaks on top of the water. It is important to use cold water as hot water makes the plaster to settle too quickly. Let the mix set for a few seconds, and using the hands start mixing the mixture until it thickens. 

Figure 1. Process of mixing plaster by Ms Claire.

Once the plaster is ready, using fingers, flick the plaster mix onto the surface of the formwork until it creates a layer. The video below shows how plaster is applied on the surface of the formwork. 

Figure 2. After plaster is applied on the surface of the mould.

The pictures below show how plaster can be casted on surfaces made by clay, and wood. 

Figure 3. Different moulds that plaster can be casted onto

Figure 4. Plaster casted on one of the clay moulds. 

Conclusion

One of the important things I learnt from this workshop is to know that laser cut wood or cardboard model can be as a mould or formwork to create an artwork or piece using plaster. Therefore it would be interesting to create a laser cut model using digital printing workshops, and using that as a mould to cast a model in plaster.