Injection Molded Yoyos

Cap mold, version 1 with complicated runner system

Motivation:

These yoyos were the final project for my design and manufacturing II class. They were a group project.

Description:

The yoyos are based off of the game of life spinner. The yoyos have three injection molded parts, a cap, base, and finger ring. They also contain one thermoformed part, a spinner. The cap is press fit onto the base and the spinner is a loose fit. I was responsible for the master sketch (which included the press fit) and cap surface modeling. I also did the CAM for the cap mold and helped review the CAM for the base mold.

Lessons Learned:

Parts vary over the course of a production run, so having accurate tolerances on parts is important. I also learned a lot about CAM during this project. We ended up using a magnet to hold a bolt in place to over mold a nut into the base. The cap began with a complicated runner system in order to avoid ejector pin marks on the underside of it near the press fit, but we ended up abandoning that idea when the piece would not eject.