Rapid Prototyping: Yo-Yo and Tilt-Maze | April 2017

Rapid prototyping refers to a group of techniques engineers use to quickly manufacture parts or assemblies. Over the spring of 2017, I designed and fabricated a yo-yo and tilt-maze to get better acquainted with several common methods of rapid prototyping. Through these projects, I gained familiarity with injection molding, laser printing, and CNC Milling techniques. Both toys were modeled in SolidWorks 2016.

HSMWorks is an extension for SolidWorks 2016, which allows a user to generate CNC tool paths in order to automate the manufacturing process for a milled part. After designing my tilt maze in SolidWorks, I used HSMWorks to create the tool paths required to mill the part from a precut piece of acetal bar stock. I also generated machinists drawings for each side of the maze, and I laser printed acrylic snap-fit lids for both sides as well.

SolidWorks Rendering of Maze Top

Click Here to View the Machinist's Drawing for the Top of the Maze

The maze was double sided and included through holes which would force the player to flip the stock several times as they played. Additionally, I designed and implemented "trap" holes which would only allow a ball to pass through in one direction. These trap holes sent the player back to the start of the maze, which added another layer of complexity to the toy.

Final Acetal Maze

The SolidWorks Mold Tools toolbar can be used to design a mold for an initial part file. In order to manufacture my yo-yo, I used SolidWorks Mold Tools to generate part files for the core and cavity of a yo-yo mold, based off an initial part file I had made for a yo-yo wall. I then used HSMWorks to generate the tool paths required to CNC mill the molds.

Aluminum Yo-Yo Mold: Cavity (left) and Core (right)

The molds were milled from aluminum bar stock and the yo-yo walls were fabricated with an injection molder in the Thayer Machine Shop. During the initial molding process, some flashing occurred which reduced the number of usable parts produced from the procedure. Using the injection molder, however, allowed me to produce many parts quickly and ultimately several usable yo-yo walls were recovered from the aluminum molds.

Flashed Yo-Yo Wall in the Mold

Assembled Yo-Yo

Trying (and Failing) to Walk the Dog with my Yo-Yo