KW
Casting the Prosthetics
On this page I have included the research that I conducted before chosing the material that I will cast the prosthetic peices out of and similarly the way in which I will cast the prosthetics. I have looked at the two techniques, Injection filling and hand filling, also the different materials, from silicone to cold foam and foam latex. I have discussed the pros and cons of each material. After this there is photographic evidence of the casting process that I used for the prosthetic pieces.
Debreceni.T. (2008) pg165-167
I have conducted this research into the methodologies for filling moulds in order that I achieve the most successful pieces from the prosthetics. I have looked into injection filling and hand filling as these two are the most prevelant techniques. The Special Makeup Effects book has a lot of information concerning the techniques to do these techniques. The injection method seems as though it would be the most successful, as the moulds are already bolted together and just need tightening, however it leaves a hole where the syringe is inserted into the mould. This means that the piece may have a blemish, however this can be patched up to create a neat finish. These pages have information concerning the silicone casting of a piece. I had completed a relatively simple cast for the last project using the injection method. I have learnt from this project that it is a good idea to use car body filler to cement a pipe in the injection hole this way the pipe fits perfectly into the fibreglass and will not come out when trying to cast the piece. Using a large injection tube to fill the mould is the best approach as you will not need to refill the tubes and potentially allow into the mould.
Bleeder holes are a component that I am relatively new to this project, they are small holes drilled into the core of the mould that allow silicone out of the hole when it has filled to the point of placement. Bleeder holes should be placed in areas where there may be a tendancy for air to get trapped. It will allow you to see how far the mould has filled when the silicone started to pour out, at this point one should fill the hol with a small piece of clay.
As a small part of the project I wanted to create a vacuum form versino of the face and the head to rest my prosthetic pieces onto after creating them. However I found that the head cast was too large for both machines therefore it was not possible to create a head replica. This is explored further in the section where I created the cap for the horn to be attached. I was able to create a vacum form version of the face, however due to the undercuts in the fibreglass it meant the plastic waspulled too tightly in some attempts at using the machine.
Here are some photographs from casting the face piece in gelatin and silicone. I first ran the piece in gelatin to remove any dirt and to see what quantity of silicone I would need for the casting. I then ran the face piece using super baldiez cap plastic as an encapsulator which worked very well except for the cap plastic coming off the nose area on the piece. I then tried numerous times to run the cap plastic in the mould, however it was notpeeling away nicely with the silicone after running the pieces. I therefore decided to run the piece in pure silicone without cap plastic and apply this to the face. This is the final facial appliance that I used for the application for summative and filming.
I wanted to research into alternative materials to use for the casting of the appliance, howeer as we have no access to a foam latex oven I was unable to use this as a material for casting the appliance. I then began to research into other potential routes, one that I came across was cold foam. I called PS Composites to ask if they had opinions on the material and I was told under no circumstances to use it on the skin. However this segment that I ound in Todd Debrecini's book notes that it is a potential product. According to Special Makeup Effects the material is essentially the same as foam latex except that it does not require an oven to bake. After the phone call to PS Composites I am wary of using it, however I would like to get a second opinion from a professional in order to fully understands its limitations and possibilities. As I felt that it would be very difficult to use a product with two minds about its uses I felt it safer to use silicone. Similarly there was not enough time or budget to experiment with the material before assessment that would allow me to create two sculpts and moulds if it were to fail.
Debreceni.T. (2008) pg176-179
This is a very helpful book, the details of the enitre process and helpful hints and tips are given to the reader to ensure that the results will be a sucessful as possible considering the reaser follows the book.