This morning, the mold makers we contracted to produce the cast aluminum rotational mold for the S4’s twin-hull part (we’ll use the W700 saddle for this product) sent us this picture with a technical question, and we thought that some of our blog readers could be interested to see it:
What this image shows is the rear part of a large size bloc of solid wood, from which a computer-controlled cutting machine called CNC Router cut the form of the S4 that we designed.
The CNC router took the information it needed for cutting the wood out of the Computer Aided Design (CAD) file that we produced with a CAD software program.
Once all adjustments and polishing are done, the mold makers will coat the solid wood pattern (dubbed ‘plug’, or male mold), and use it to produce two concave molds called ‘sand molds’, into which they will cast molten aluminum. One of these molds will have the shape of the top part of the S4, and the second mold will have the shape of the bottom part.
These two parts will be used to make the aluminum mold (tooling) for molding the S4’s twin-hull part.
That aluminum mold will be polished and coated with Teflon, and the mold makers will encase it in a steel frame they will build around it.
The steel frame will enable attaching the rotational mold to a large size rotational molding machine that will rotate it in a rotational molding oven big enough to allow for this truck-size object to move freely in all directions.