If you wish to keep the clay impressions then carefully peel them away from the plaster. The clay can be fired afterwards.
When the clay has been peeled away, you will be left with a solid impression from your clay surface.
I will be using my plaster casts to create silicone rubber impressions. To see the final step in this three part process, please view my next post on Experimenting with silicone rubber.
Step two – working with clay / plaster casting
To view the first step in this process please see my previous post on Working with clay.
Once I was satisfied with the markings on my clay pieces it was time to cast them in plaster.
If you are new to plaster casting and would like to try it for yourself follow the instructions below.
What you will need:
Cold tap water
What to do:
- Half fill a mixing bowl with cold tap water.
- Sprinkle a hand full of plaster powder into the bowl.
- Repeat this step a hand full at a time until the plaster begins to form a heap onto of the water’s surface.
- Once the plaster powder has formed a heap, stick your hand into the bowl and begin mixing the plaster with the water.
- Break up any lumps you can feel.
- If the mixture feels runny you will need to add more plaster (it should be the consistency of double cream.
- Once the desired consistency is reached, dribble handfuls of plaster over your clay moulds.
- When you have covered the clay with a thin layer of plaster, gently give it a shake to disperse of any air bubbles.
- The surface of the plaster will begin to thicken and become cheese-like. Use a ruler to square off any spillages of plaster.
- Dribble another layer of plaster over the first layer and repeat until you have built up about four layers.
- Use the ruler again to square off any spillage’s.
- Cover with clingfilm and leave to set for a few days.
To view the final steps in this process please see my next posts on Plaster casting part two and Experimenting with silicone rubber.