* Plastic board * Face cast
* Clay * Protective gloves
* Alginate * Small bowl
* Separate bowl with lukewarm water * Plastic cups
* Plaster powder * Hessian
* Scissors or sharp sculpting tools * Silicone
* Catalyst * Spatulas
* Scales * Thixotrophic (thickening agent)
* Medium size pain brush * Paper towel
* Modroc * Vaseline
1. In preparation for moulding, you need to make sure that your face cast is level. To do this, place your face cast onto a plastic board and look down the nose of the cast. This way you will be able to tell if it is on a slant or not. If the cast is slanted build up the side with clay so it is even.
2. As my cast was on a slant I needed to hold my cast level, and then placed clay underneath the sculpt to even it out to create a 'bed' for your sculpt to sit on. Make sure all the sides are smoothed on to the board and onto the sides of the cast. This keeps it secure and prevents the cast been damaged during the moulding process. Once this is done start to create a wall around the bed of clay and the face cast.
3. Once you have smoothed the clay, press holes into the bed of the clay round the cast using your finger. This acts as a 'key' to lock the mould and the life cast together in later stages.
4. For the first step you need to place the face cast on something where it is not going to tip/tilt over as the face cast will be getting filled with plaster. For these next few steps I have steadied it onto a bucket.
5. Before mixing and pouring the plaster into the face cast, I had to re-sculpt the nose of my model. Unfortunately he found it difficult to breath whilst in the cast, so the nose area was kept clear of the alginate.
6. To rebuild the nose I used left over alginate which was applied to the tip of the nose by having the alginate in my hand and carefully placing it in the alginate. Make sure that the alginate doesn't seep into the nose as this will lose any facial details. I then left to dry for a few minutes.
7. Before mixing the plaster use a small bowl and fill it half full with lukewarm water. Taking a plastic cup fill to the brim with plaster and gently sieve over the bucket you have just poured water in.
8. You want to create an island in the water whilst sieving the plaster. The water will then absorb he plaster powder and you can then start to mix by hand, to get rid of any lumpy textures . Make sure you are wearing gloves for this!
9. Now that all the lumps are gone, you can now start to apply the plaster to the cast. Gently pour small amounts of plaster each time into the cast. Each time you must tap the sides of the cast to ensure all air bubbles rise to the top of the surface and then add more plaster.
10. Make sure that the plaster is not filled all the way up to the top of the casts this will make it incredibly heavy! I would suggest filling it up with plaster just over half way, but it will still have a lot of weight to it.
11. The plaster will soon start to get thicker so place your hand into the mix and start by spreading the plaster up the side of the cast to even out the plaster and make the sides thicker. Make sure you do this a few times so it becomes level.
12. Now you can start to layer Hessian into the plaster. This will create a more stronger cast and will less likely break. Another layer of plaster is added over the Hessian and is left to dry for 5-10 minutes while the plaster goes through the cooling process.
13. Now the plaster has dried the plaster 'jacket' can now be removed. To remove cut through the Modroc and start pulling the layers off until you reach the face cast underneath.
14. The next stage is creating a flexible mould. For this you will need to mix together two liquids (silicone and catalyst).
Start by measuring 100 grams of silicone to a plastic measuring jug. Using a clean plastic cup measure 10% of the catalyst, which means 10 grams will be added into the mixture.
The catalyst is a bright red liquid which makes it easier when it comes to mixing them both together. The liquids need to be mixed thoroughly using a wooden spatula so that all the white substance turns to a light pink colour. Pour the contents into a clean cup and thoroughly mix again, getting rid of any white liquid.
15. Now drizzle a small amount of Thixotrophic to thicken the mix. You can now start to apply to the face using your finger to push the mix into the eyes and nose area. This will also help the air bubbles to escape.
16. Using a brush apply using a brush over the cast to create a thick layer and smooth over the face. Make sure the 'keys' you created in the clay are also covered as well.
17. Damp a paper towel and pad on the mould to neaten out any brush marks and the leave to set.
18. The last few processes of moulding part one is to cast the final mould. You will need to create a Modroc jacket to ensure the moulds solidity.
Going back to the casting the face, it is the same technique only this tie it is done in two halves.
This makes it easier when it comes to removing the mould.
19. Using the Modroc again, apply to one half of the face. Once you have done this apply a thick layer of Vaseline in top of the inside edge. This prevents the other side from sticking together.
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20. Now Modroc the other side, and carefully go over the side you have previously done. Leave this until it is set.
21. Once this is done place the cast somewhere that will keep the mould secure while you pour in the plaster. For this I used a bowl.
22. Fill a plastic cup with plaster and pour into the face cast and then leave in a safe place to dry. Make sure this cast is hollow so don't make it as thick as the previous one.
23. Now that it has set, carefully crack and lift the Modroc jacket off the mould.
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24. Once the mould has dried you can start to peel away the edges to reveal the final cast. This cast will then be sculpted onto for my prosthetic piece!
Head over to, 'The Sculpting Process' for the next steps!
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