As part of my Integrated CAD/CAM/CAE class, I designed a tool to help wind in new strings on my guitar. I was tasked with making this part using 3 separate manufacturing techniques in progressive stages: Objet 3D printing, urethane molding and injection molding.
After designing the molded part in SolidWorks, I performed simulations to ensure that I had the appropriate draft angles on the relevant surfaces. The first prototype of the part was 3D Printed using an Objet, which allowed me to get a smooth finish on all surfaces.
I then made a two-part Silicon Rubber mold around this part. This required several iterations, as we encountered issues with bubbles forming inside the mold, and the mold failing to separate from the part in several instances.
We then poured urethane into the silicon rubber negative, to get a finished urethane molded part.