Composites

Acknowledgements

Would like to thank Dina for helping me with the compositing process.

“Composite materials, often shortened to composites, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or microscopic scale within the finished structure.”

- Wikipedia
Composites are created by combining two materials together to create a third hybrid material. The basic idea is to take two materials that complement each other, one strong and brittle material could be mixed with a weaker more flexible material, to create a material that is both strong and flexible for example. Think rebar in a concrete bridge.

For the project this week, I decided to make a composite mummy mask. I planned to use canvas strips with white SmoothCast 305 (7 minute pot time, 30 minute set time).

The process was simple.
Model a generic face using a surface modeler, modo.
Mill the foam using the ShopBot to produce a 3D face.
Mix SmoothCast and cut canvas strips.
Create a vacuum bag using plastic and silicon.
Place cotton on top of plastic bag, then pink plastic mold release, then the face I milled.
Dip strips of canvas in SmoothCast and layer on top of the face.
When finished, add another plastic mold release and another piece of cotton.
Finally seal the vacuum bag and insert the vacuum tube.

Tips for this week

Place the vacuum tube right up against the cotton layer. This will prevent the plastic from sealing shut while vacuum forming.
If you glue two pieces of purple foam together to make a thicker piece of millable foam, use the correct glue AND make sure it dries completely. If you mill prematurely, you can’t correct your errors.