The next stage is to lay clay into the mould so we can create the core. I used a rolling pin to make some flat strips of clay of equal thickness. I then lay these into the mould. They represent where the silicon will once the mould is finished.
The plastic tube sits where it did in the original sculpture.
I added some cables into the mould. These create channels inside the core that will allow silicon to be poured in.
The mould's then clamped together and plaster is poured in. This fills the mould except for the areas where we've placed clay and cable.
Once the clay is cleared away we have a two piece mould with a plaster core. The silicon will travel down one channel created by the cables and air will escape out the other. The silicon will fill the void between the core and walls of the mould.