When beginning to prepare the sculpt for the second moulding process the edges of the sculpt needed to be softened using a wire brush to blend the edge's, this will ensure a smooth blend on the edges of the prosthetic to the models skin. As well as this around the surrounding areas of the face which has been sculpted on, a thin layer of clay was applied. The additional surrounding layer of clay should be on average 1cm away from the sculpt itself, also the edge between the 1cm gap should be approximately half a cm thick. The 'channel' which has now been created will then ensure an extremely smooth edge is created as the excess of the moulding material for the final piece will push outwards into the 'overflow'. This technique was also used when covering the eyes to ensure a smooth edge. Then all channels and areas which reveal the cast material underneath such as the keys and nostrils were coated with a think layer of Vaseline to ensure the final mould will not lock in place. Finally the detail of the sculpt was then softly dusted with talc and a very fine layer of lubricant spray was applied over the face. The first stage of preparing the sculpt for the final moulding in complete.
The second stage of preparing the sculpt to be moulded is creating a clay wall around the full cast, this will ensure that when the clay is poured over the sculpt it will stay in all the necessary areas to set. The clay used should be thick strips on average 7- 10 cm in height, the clay should be place around the edge of the cast and secured in place by blending the edges into the work surface.
To establish stability to the wall the next stage is to add two layers of plaster bandage. This in turn become the plaster jacket, created by immersing similar sized plaster bandage strips into room temperature water to active as size and width of the clay wall. once rubbed into place the plaster is left to set, this is repeated for 2 layers and left to dry for 10 minutes.
The structure around the cast is now stable and ready to be filled with plaster cast, the ratio for the first layer (the detail coat) was 1 cup of water to 2 cups of plaster. This was shared between two and added over the sculpt very gently, the constancy was very fine, this is done to allow the plaster to capture all detail which has been created throughout the sculpt. This was left to set for a few minutes whilst the second batch of plaster was mixed, this was mixed to a much thicker consistency, with 2 cups of water to 3.5 or possibly 4 cups of plaster.
The thicker plaster is then poured over sculpt to create a stable cast which will not be fragile when manoeuvred round. Also as the plaster is thicker it becomes easier to manipulate into areas of the sculpt. A layer of hessian was also over the plaster, paying extra detail to the edges of the cast as they become the most brittle.
This is then left to set for 10-15 minutes, ones set, the surrounding wall can be removed and excess plaster chipped off the edges.
The image above shows the casts after the wall has been removed, as you can see the edges are consistently thick, this will make it less fragile to work with. The two casts now need to be separated, using a strong SFX tool. The tool should be wedged between the dividing line right the way around the casts, this will ease the edges and allow air in to separate them.
Once released the cleaning process will then begin, the original cast will need the clay to be removed for the second moulding process to begin. The clay is easily removed however if small pieces become difficult, a small amount of lighter fluid on scourer sponge and lightly pushing the surface of the cast (do not brush hard as this will remove the detail of the cast). The final casting of the sculpt was a success, all detail has been picked up and no air bubbles are distorting the final design. The cast of the sculpt is now ready to be moulded. The material will be poured into the cast, then the original cast will be used to press and lock in place, the keys will ensure they stay steady whilst the material sets and this will ensure a thin and even prosthetic.
Materials for the final piece
The final stage of creating the prosthetic piece is deciding upon the correct material to fill the mould.
For the final prosthetic I have decided to create a silicone piece, after researching into both latex and silicone materials the latter fits the criteria which needs to be met due to the design.
The research revealed that a latex prosthetic creates a flat matte finish which will then need to be coloured to achieve the specific design plan. The following website shows examples of the raw latex masks and also final designs which have been created using the latex foam material. http://www.fxwarehouse.info/mm5/merchant.mvc?Screen=CTGY&Category_Code=FoamPros
Although the foam latex gives a soft finish with fine edges for blending, the matte block colouring of the material would not have been suitable. When researching the SFX book 'A complete guide to special effects makeup- conceptual creations by Japanese makeup artists' provided great examples of latex prosthetics being used and the amazing character designs which can be created from using the material. Below is one of the foam latex designs from the book which I found very interesting:
Tokyo SFX Makeup Workshop (2006) A Complete Guide to Special Effects Make-up, 1st edn., Japan: Graphic-sha Publishing Co., Ltd
This particular foam latex piece has only been slightly coloured to create definition within the bone like design which has been created. Throughout the design of the final piece, the main area of concentration has been the translucency of the skin. Therefore to create this effect less is more in terms of the makeup and the material used for the piece has needed to fit this criteria. Through reaching into foam latex, with less product used as it appears on the images above, a matte cream/ white colour which would be very difficult to adapt to appear as translucent skin. The following video is demonstrating the difference between foam latex and silicone based prosthetics within SFX makeup https://www.youtube.com/watch?v=I7yft3IhmXs. Also a fantastic video I found was https://www.youtube.com/watch?v=rJWCGyblFfI, this video explains why professionals are now using silicone and why it is preferred by many instead of latex.
Due to this, research into different materials which will create the desired translucent effect began. The use of silicone within prosthetic is very common when desiring a human flesh appearance. The following website explains and defines what silicone is http://www.dowcorning.com/content/discover/discoverchem/properties.aspx. Soft “skin” silicone rubbers, used by make-up and Fx artists, were developed for the industry and certain kinds are also used in the medical prosthetics industry. Skin coloured silicone is used within the health care services when providing patients with prosthetic hand and arm solutions. The following website explains why silicone is used for the limbs; http://www.ottobockus.com/prosthetics/upper-limb-prosthetics/solution-overview/custom-silicone-prosthetics/. The silicone creates a realistic skin texture and tone once matched to the individuals complexion and skin texture, this methodology will be used to create the translucent complexion for the final design.
As translucency and colour will be developed through the silicone, all the finer detail including the veins will be created using a very fine brush and skin illustrators to the realistic effect which is required.
Mixing the silicone and preparing both cast and mould
When preparing the cast and mould both must be fully lubricated and sealed to protect from the silicone. Although silicone is a very good material to use, it will absorb into anything if possible and this is way the fix and Vaseline spray were used to make the de-moulding process easier.
Above shows all of the sprays which had been used to avoid the silicone sticking to the mask, the first is a fix spray this ensures all finer detail is protected throughout the process. The second is a Vaseline spray to lubricate the casts and make removing the prosthetic easier. Finally the third is a silicone release spray, this is a protector for the cast again the silicone absorbing and sticking, three layers of this product were applied in preparation. All three products are very similar however all precautions needed to be taken to ensure the final moulding process was successful.
The ratio when mixing the two silicone components is 1:1, for the prosthetic we then mixed 80 of component A and 80 of component B in separate mixing cups.
A very small amount of colour was then added added to the separate components, approximately a drop of each was added to each cup to give the prosthetic a tint of colour, this would therefore mask the prominent features underneath such as the eyebrows and lips.
Component A was the added to B and mixed using a mixing stick, to ensure all of component A had been poured out the mixing stick was broken at the end to create a flat edge making the mixture much easier to scrape out of the cup. All for the component A needed to be added to ensure all of the earlier measurements were still equal.
The mixture was then poured into the mould very gently, ensuring all detail had been captured by pouring onto the sides of the cast and allowing the silicone to run into the fine detail.
After this the original cast was placed into the mould and locked into position using the Keys. All excess product should be constantly squeezed out by the original cast, this will create fine edges which will makeup the prosthetic much easier to blend on the face. Through adding pressure onto the mould the silicone will ooze out and set into position, this should then be left for 20minutes to set.
After the silicone has set the moulds then need to be taken apart to reveal the final prosthetic, this can be a long process depending on whether the silicone has become stuck to the cast. The two casts now need to be separated, using a strong SFX tool. The tool should be wedged between the dividing line right the way around the casts, this will ease the edges and allow air in to separate them.
Although I am very happy with the colour and detail which has been picked up by the silicone, the edges of the prosthetic are far to thick and will blending to the sick very difficult (image below). This is due to the piece being to thick and not enough pressure being held onto the casts as the mixture set.
A second prosthetic was then created developing from the first mould, a deadener was added to the mixture which made the consistency of the piece softer and easier to apply. Also more pressure was added to the moulds as they set in place, this was created by attaching clamps around the edge of the casts the squeezed additional excess out of the mould. This was again left to set for 20 minutes. This was then realised and revealed an improved prosthetic which could be used on the day of the assessment.
After numerous efforts to create a soft edges on the prosthetic, using the press and squeeze technique to create the final piece has not produced the piece to the standard required. Due to the suction created when pressing the two moulds together excessive air bubbles were developed which ruined the piece as a whole. As well as this due to the suction the air within the silicone made releasing the moulds extremely difficult, after multiple attempts both plaster moulds were becoming damaged. Because of this an alternative technique needed to be used to avoid the problems which occurred.
An injecting method was then used to reduce the amount of air bubbles and suction created with the silicone. For the two plaster casts needed to be heavily lubricated to enable the release of the prosthetic much easier.
Prior to the lesson my tutor has drilled necessary holes through the two castes to allow the excess silicone to ooze through, this will again push any unwanted air bubbles out and created finer edges on the piece. The small holes were drilled evenly around the cast including a centre holes in which the silicone would be injected.
Vaseline was firstly applied to the casts using the tips of the fingers ensuring all areas were covered to allow all finer detail to be captured. As well as this a layer of mold release wax was applied using a paper towel, again reaching into all finer detail.
After this the plaster mould and cast were placed back together and locked in place with the keys, they two casts were then placed over a bucket for stability. This ensured the silicone would spread evenly through the mold. As well as this a safety harness was attached around the casts, this was to secure the two casts together and also again create finer edges because of this.
The silicone was then mixed in exactly the same was as the previous attempts however a larger quantity was mixed to allow the extreme excess to push all air bubbles out. As well as this no additional colour was added to the piece, this was due to the colour pigments added hardly any colour to the previous pieces and the own colour of the silicone worked well for the character design.
The silicone mixture was then poured into the syringe and slowly pressed into the mold.
Once all of the silicone has been injected into the mold, the excess mixture began to ooze from the holes which had been drilled. This made the evaluation of if the mold was full and even much similar as all of the holes and edges oozed, making the molding process a success. The silicone was again then left for 20minutes to set.
The cast and mould were then released using the same method as previous, using a strong SFX tool. The tool should be wedged between the dividing line right the way around the casts, this will ease the edges and allow air in to separate them.
Above are the image of the final piece which has been created from injecting the silicone into the molds. The piece which has been developed is a huge improvement from the previous attempts, the edges are very thin and no air bubbles have formed. I am incredibly happy with the prosthetic and worry began to set in as the silicone was not working as hoped, this would have then forced me to use for latex instead and through the knowledge from research this would have not been suitable for the design being created. However after reflecting and improving the method a very good piece has been created for the assessment.
This piece now needs to be painted in preparation for the assessment, this can be found under 'The finer detail' page of the blog.
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