PLASTER WORKSHOP 3

PLASTER

Plaster and clay - 21st November 2017

The session was a one to one session with the technician Ms Claire on discussing about the formwork I have created and how it can be used to make a plaster model. 

The picture below shows the final mould that I have created using wood. According to the previous lesson, before the session began I applied petroleum jelly as a release agent on the surfaces of the formwork. 

Figure 1. Wooden Formwork 

However, after assessing the mould, the technician explained that the formwork I made may not be so successful as a mould as there are too many undercuts and this may obstruct the plaster to come off once it is casted. She also explained different ways I can use this formwork to create a clay mould on which I can cast a plaster model. This plaster model will then be used as the mould to cast the final piece. 

A thick piece of clay was rolled onto the wooden formwork so that the clay sits into the voids of the formwork. But since the wood has been coated with a release agent, it was difficult to get the best results with the clay. 

Figure 2. Wet clay is rolled before taking 

The picture below shows the clay mould after it has been peeled off from the formwork. 

Ms Claire advised that I can try to shape the clay using the shaping tools to create a form that I wanted. This was one of the advantages of using clay as a mould, as it can be shaped into any form. 

Since the clay that was used was quite wet, the clay mould had to be kept to dry before any shaping. 

Conclusion

Though I was not successful in using the laser cut formwork for casting a plaster model, the session introduced me to different ways I can use the formwork to make a clay mould which can then be used for a plaster cast. Next time, when I am working on a plaster model, I will be careful with the type of material I am using to make the formwork. In addition, its important to identify whether the use of a cast is the most appropriate method to use for any specific project that I am working on. Because otherwise, depending on the kind of project, I may not be able to get the most effective results. For example, if my model has a lot of undercuts, a laser cut wooden formwork may not be the most ideal mould to use to cast a plaster model.