Foam model prototypes were created using hot wire cutters and hand tools such as a dremel, with finer details and smooth finishes were achieved using sand paper. A CNC machine was used for larger, more detailed projects including my honours project where a negative mould was created to use for casting.
3D printing machines such as the Makerbot (FDM), Projet 4500 (CJP) and Objet Connex (PolyJet) have been used to create high-fidelity prototypes. To finish the 3D printed part, different models have required sanding, priming or painting to achieved the desired effect.
Using a negative foam mould and a material called Jesmonite, a final model was cast. Initial attempts resulted in leakage from the mould, which led to a re-design of the 2 part mould using a lip and groove to create a seal. Manufacturer instructions for sealing were followed by coating the foam mould with chip fat, which also acts as a release agent. After preparing the mould, it was assembled and clamped together ready for pouring.
Images above (middle) show the material after it was removed from the mould (first), which would then be sanded...and sanded some more to reveal the creamy white finish with coloured pieces of fleck breaking through.
In collaboration with the Jesmonite cast parts, the final honours model used waterjet cut 3mm aluminium. The hummingbird feather-pattern inspired mesh and drawn in Solidworks using sheet metal features and exported as a DXF file, ready for cutting. The middle picture above shows the initial stages of cutting, while the image to the right is the final, hand-bent piece.