The next step after making the plaster base is to sculpt my design onto the face using plasticine. I didn't want to create an over complicated sculpt that would take me all day to stick on so i kept it simple and designed my character to be an old witch/old hag.
As shown in the image above i created an enlarged nose, with warts, and a furrowed eyebrow. I have also placed a clay wall around the base which is an inch or two taller which will hold the plaster mould on top, to secure this i added some mod roc around the edges to stop any plaster leaking out through the clay. I also added vaseline to the plasticine to stop the plaster sticking to it once it is applied on top of it.
The next step was to mix up a bowl of plaster, my favourite part as i love the feel of getting my hand in and mixing the plaster, i poured a small amount into the base and used a brush to ensure it covered all the sculpted areas, slowly building up the plaster a bit at a time.
Once the first layer was on it was time to add some skrim for extra strength following the same methods as before, pressing the skrim into the plaster and using the brush to ensure it is all covered.
As my sculpt has an enlarged nose i had to ensure that this was strong and study enough to not break if dropped so i applied 2-3 extra layers of skrim just to the nose piece before adding one extra layer of plaster over the top and leaving it to set for 30-45 minutes.
Once it had all set i cut away the clay and mod roc wall and prized the two halves apart. Note the bumps in the top mould... this is so when the two halves are placed back together they will always go back together in the same place. To finish up I removed all the plasticine from both the cast and the mould ready for the next step.
Another thoroughly enjoyable lesson with so much learnt in one day, i feel confident mixing and using the plaster to create moulds and the techniques learnt in this lesson can be applied to any similar kind of sculpt, as the base remains the same it can be used time and time agains to create more prosthetic pieces.