Senior Squad

Over the past week, senior squad has been working on our go-to-manufacturing report. We used the results from our Moldflow analysis, to scale up our CAD models by about 1.2% for each part, except for the antenna which had a higher shrinkage percentage of 2.7%. We then made CAD models for the molds for our injection molded parts, and their respective CAM toolpaths. In parallel, we worked on a bill of materials for each stock material we would need for the entire manufacturing process, and we also drafted up a layout of our factory. Here are some of the key results: Part Material Quantity Process Cost Per Yoyo Total Base Polypropylene 27,000 lbs Injection Mold. $0.06 $27,000 Sand Polyethylene Terephthalate 88,800 m 2 Thermoforming $0.07 $69,132 Patrick Polypropylene 7,000 lbs Injection Mold. $0.02 $7,000 Rock Polypropylene 25,000 lbs Injection Mold. $0.04 $25,000 Antenna Polypropylene 605 lbs Injection Mold....

We recently used the Moldflow software to analyze our injection molded parts: Patrick, the base, the rock, and the antenna. The most useful information we received was the shrinkage: Base: 1.28% Rock: 1.20% Patrick: 1.28% Antenna: 2.67% We also gained important information on the cycle time, which we can use moving forward when working on our factory layout. If you are interested in seeing more of our results, you can check out our Moldflow report here: https://docs.google.com/document/d/1e6q5_iBeC9F7JpJ_XUnGs-icJlVAsYjP-zRTd4GQ9dk/edit?usp=sharing

After the design review, we looked through the feedback we received in order to make some changes to our design.  The major improvements include: - Adding an extrusion under the center of the rock to allow for a better interference fit with the antenna. - Add a locating feature to the base and Patrick to secure him into the base. - Thermoform the layer of sand, and  have it sit underneath Patrick. - Injection mold Patrick, and place stickers on him for his eyes and underwear (he will no longer be wearing shorts, as seen below):

While it has been a while, we wanted to take a look back at our design review! The main goal of our yo-yo was to show Patrick Star living under his rock. Each of the two sides of the yo-yo would be Patrick living under that rock. In order to do this, we decided our yo-yo would be made of the following parts: We decided to injection mold every part except for Patrick, which will be thermoformed (this design choice has since changed, but this was our decision at the time of design review). In order to get a sense for what the yo-yo would look like, we 3D-printed one side of the yo-yo, and here is the result! For more on our design review, you can view our presentation here: https://docs.google.com/presentation/d/18DHTvW9kK-wbNYPmfx5LZZFfujo952XgDPKz3XcQQc4/edit?usp=sharing