Blog Deliverable 4

  Glow-in-the-dark snap-fit center. Grooves around the upraised triangles to allow for another snap-fit part and consistent outer radius allows for snap fitting into the base. In total, was a great success of a part.

   Blue version of our Yo Yo base. Consistent inner radius allows for the snap fitting of other parts inside it. In total went very smoothly.

   Our "Spider" snap-fit piece. We often had problems with weld lines and an inability to pop this piece of of its mold (as it would stick onto the triangles and oval). We could improve this piece by increasing the draft on the triangles so that it doesn't stick in the mold as much.

 One of the thermoformed parts. These all came out very well and snapped perfectly into the center of our yo-yo.

 Our completed yo-yo from the back. The clear triangles are glow-in-the-dark!

  Finally, our completed yo-yo from the front! What a pretty yo-yo.

Specifications Comparison Sheet
Specification	Planned Dimension	Measured Dimension
String Groove	.25” +/- .005	.058 +/- .01	Didn't meet design specifications because we shortened the string gap after manufacturing
Base Inner Diameter	2.25+0.0/-.005	2.245 +/- .002	Part was easily injection molded and met specification
Snap Fit Part 1 (Triangles) Outer Diameter	2.21''+.005/-0.0	2.26 +/- .001	Part was easily injection molded and met specification
Snap Fit Part 2 (Spider) Outer Diameter	2.21''+.005/-0.0	2.26 +/- .002	After much tinkering with the injection molding, part met specification
Mass Base	13.12 g+/-10%	15.5 g +/- 8%	Part was outside of design mass, but consistent
Mass Snap Fit Part 1 (Triangles)	9.71 g+/-10%	7.5g +/- 4%	Part was outside of design mass, but consistent
Mass Snap Fit Part 2 (Spider)	2.11 g+/-10%	2.4 g +/- 10%	Part was outside of design mass, but consistent
Mass Thermoform Right	.348 g+/-10%	.340 g +/- 10%	We made multiple runs until we got the process to the point where we liked it.
Mass Thermoform Left	.3812 g+/-10%	.392 g +/- 10%	We made multiple runs until we got the process to the point where we liked it.
Mass Total	. 05078 kg+/-10%	.0541 kg +/- 10%	Since all of the parts were consistent, the whole was consistent.
Max RPM	.047m/s+/-10%	3350 RPM	Roughly what we calculated!

Summarized findings in Deliverable 4 of the "Triangles" Insert

The Triangle Insert's critical dimension was its out diameter, which we needed to control to snap fit the part into the base of the yo-yo. We found this dimension to have a UCL of 2.265 inches and an LSL of 2.255 inches. All of our parts were within this range and thus our part snap fit in successfully!

Link to Deliverable 4:

https://www.dropbox.com/sh/ata8l7eibfgm1lj/2GHzJ_hOIX