master of design thesis
I discovered and explored the concept of an "engineering designer" in my Master of Design thesis. I designed and manufactured a chair by combining engineering and design methodologies using paragon midcentury modern thinking as a basis.
Injection molding was selected as my process for its unique and challenging constraints. This process needed to be converted to a small scale craft. Steel molds were replaced by nonstick plastic, which was cheaper and easier to machine. Molten plastic was replaced by a two-part casting resin. A molding machine was replaced with screws to provide clamping pressure. This was tested in the small-scale mold pictured above.
The resin was degassed before pouring into the mold in atmosphere. After the initial pours, cups were added to provide additional back-pressure to fully fill the mold. It was also noted that risers were needed to prevent shrinkage from causing part defects.
The test mold showed that the process was successful. I experimented with composites by adding fiberglass to enhance the structure.
Initially, I was curious about making a bi-material product. I machined an open-face plastic mold and experimented with a resin and plywood combination. This was successful but not used in the final direction.
I chose to make a chair since it is challenging in both engineering and design terms. I ideated based on three different interpretations of a "plastic chair."
Exploring plastic joinery.
Iterating on a fully plastic chair and beginning to introduce CAD models.
Pivoting to a bi-material chair for better load-bearing capacity.
Pivoting again to a proper load-bearing structure and more adherence to tradition injection molding.
Zeroing in on a ribbing system.
Scale prototype and human factors research.
Finite element analysis to finalize chair leg shape.
Final design direction.
Designing molds for the leg cover, seat back, and seat pan.
Machining the molds.
Molding parts using the funnel as a cup and straws for risers.
Parts were trimmed and then assembled together.
The final chair.
My insights.