Investment Cast Bottle Openers
In my final quarter at Cal Poly, I had the opportunity to take Advanced Metal Casting (IME331) in the manufacturing department. My experience to casting prior to this class consisted of a single lab taken freshman year, that involved little to no design work. This class, however, dove deep into details around design for casting, runner and gating design, mold and pattern making, and more! I decided that for our main design-build project, I wanted to make a set of custom bottle openers, inspired by a design I had seen online. This page details the design and manufacturing of these bottle openers, with many of the lessons I learned along the way.
Part and Gating Design
Using SolidWorks, I designed the part shown in the image above. The opener featured a keyring hole on the end, and the lettering of a mantra “it is what it is.” For the castings, the solid flask investment method was to be used with 3D-printed patterns. As I designed the part and gating, I kept in mind the need to 3D print them as patterns first. This lead me to break the sprue and runners into three parts that would be glued together, allowing for easier printing. I also modified the parts themselves to be able to snap onto the gating tree. These are shown in the images from CAD below.
Flow and Solidification Simulation
Once the initial gating concept was finished, it was validated using SolidCast flow and solidification validation.
Pattern and Mold Making
I made the patterns using FDM 3D printing with PLA. If I were to go back now, I would have printed this using an SLA printer to get much higher resolution in the layers. With FDM you can clearly see the layer lines, which show up in the final casting. With this pattern, I mixed the plaster slurry and created the investment mold. Then, I fired the mold, melting out the plastic pattern and leaving a hardened mold for metal casting.
Casting and Final Parts
Below are photos of the completed parts! Notice how you can clearly see the layer lines from the 3D prints. While I would love to see this removed, it does clearly show how this part came to be - which I think is pretty neat! I also was quick to confirm that they do in fact open bottles. Success.
