Through the use of rhino 3D modelling, I made complex surface that would allow me to see what marks would be created when a form cut by the CNC, through a range of ungulates curves.I began by first cutting into blue foam which is a cheap material that could be cut fast and create a rapid prototype; approximately 5O minutes completion time.
Using this I then applied multiple layers of PVA glue to coat the surface, allow me to cast in plaster without the porous material sticking. Creating a positive and then a negative.
Through this rapid prototyping and application of glue i lost a great level of detail, something I was keen to retain and explore in my work. To counteract this I decide to CNC directly into damp plaster, that the dry would give me a mould that I could pour directly into. This took far longer due to the material density and the increased tooth path of the CNC; 5 hours completion time. This time factor is something i will have to take into account when producing my moulds.
CNC machining directly into the plaster, although took 6 ties longer to make. Gave me a far better mould with high detail that I would be able to capture in slip casting. The photo below shows the mould next to each other and you can clearly see the quality difference.