Mass-manufactured latte yo-yo

Final manufactured yoyo with and without cup


Roles: Mold Design (3D Printed and Machined), Manufacturing (Injection-molded base)
Skills: Design for Manufacturing, CAD (SolidWorks), CAM (MasterCAM), 3D Printing, CNC Milling, Injection Molding, Quality
Time: September - December 2018

Developed as part of 2.008, Design & Manufacturing II

The Problem

The goal of this project was to design a yo-yo for manufacturing at scale.

Due to a shared love of coffee shops, my team designed a yo-yo based on a latte. The yo-yo required a base with a fitted metal shim for weighting, a snap-fit between the “coffee” and the base, a fit between an injection molded “coffee” and the thermoformed part “foam”, and a thermoformed “cup.”

The Process

The yo-yo was first modeled using SolidWorks. CAD model of blue yoyo with brown coffee and white foam art that looks like leaves. CAD model of yoyo sitting within white cup. Exploded view of yoyo parts (cup, base piece, connector, shim, foam piece, coffee piece).

This model was then used to design the molds. MasterCAM was used to create the toolpaths for creating the molds from aluminum and then the molds were made using a CNC mill and a CNC lathe. A mold was 3D printed using an SLA printer for thermoforming the “foam.” CNC milling the mold for the yoyo base piece. Finished yoyo base mold with magnets to hold the shim. Finished CNC milled mold for the coffee piece with a negative pattern for the latte art.

Test runs were conducted for all of the parts to optimize the process parameters and ensure the parts fit together as desired. The molds had to be modified a couple of times to improve the snap-fit. Finally, we did a production run and produced 100 of each part (50 of the cup) and assembled 50 yo-yos. Layout of parts to assemble 50 yoyos.

The full process is shown in the video below.

The Result

The final yo-yo is shown with and without its “cup” below. The yo-yos were subject to a drop test to ensure that they did not fall apart. Final manufactured yoyo without cup Final manufactured yoyo inside thermoformed cup