Our Yo-Yo Design


Our Yo-Yo consists of two injection-molded parts, which fit together through a press fit. The base part contains the nut to join the two halves together.
There are also a wooden ring and a cut and edged stainless steel part presenting the skyline of Boston on one side and the skyline of MIT on the other side. These parts are insertion-molded into the plate part of the Yo-Yo.

The steel plate will also be edged with the following details:


 Additionally, we will have a thermoformed base which allows a nice presentation of our Yo-Yo (as seen in the first picture).

 For each of our major components we first sketched out a rough sketch of what we ideally wanted the piece to look like and what function we wanted it to have.  From those initial sketches we then took into consideration what alterations or details would allow for an improved design for the manufacturing process.  For example, our yo-yo will have an inlay piece with many small details etched onto an otherwise smooth surface.  From what we had learned in class about different techniques we could use our team concluded that laser cutting would be the most time efficient path that allowed us the level of detail we are aiming for.  Also, when designing our injection molded pieces we took into consideration how to best create a uniform thickness and how to prevent needing small areas to be injection molded as part of a larger piece (since we know many challenges could arise with small pegs sticking out of a larger injection molded piece when it comes to cooling and setting the specifications for that injection molding run).  Additionally, we paid attention to not have any overhangs or side details for the injection-molded parts. We also knew that our stand would be less complex when it comes to small details in comparison to the overall yo-yo (and could function perfectly with an overall thinner thickness than our planned injection molded parts) and it was for that reason that we felt that thermoforming would be a good avenue to follow for the base stand.
Table of Specifications

Part
Critical Dimension
Target value
(in inch)
Target value
(in SI)
Tolerance
How to measure
Moving plate
Outer diameter
2.06 in
0.052324 m
+/- 0.005 in
(0.000127m)
Calipers
Base plate
Inner diameter
2.30 in
0.05842 m
+/- 0.005 in
(0.000127m)
Calipers
Wood Ring
Outer diameter
2.30 in
0.05842 m
+/- 0.005 in
(0.000127m)
Calipers
Metal plate
Outer diameter
2.00 in
0.0508 m
+/- 0.005 in
(0.000127m)
Calipers
Base
Width of pocket
1.25 in
0.03175 m
+/- 0.005 in
(0.000127m)
Calipers
Assembly
Outer diameter
2.50 in
0.0635 m
+/- 0.005 in
(0.000127m)
Calipers
Assembly
String Gap
0.08 in
0.0002032 m
+/- 0.005 in
(0.000127m)
Calipers


 Link to our team's schedule and Gantt chart:
https://docs.google.com/spreadsheets/d/11FblMBH4sf9gtoY_AJCwPPAXdZkmJIWneeS1p_ZpjLU/edit?usp=sharing

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