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The Die Cast Factory
The Concept and Prototype
The corporate marketing vice president (VP) charged a new product development team with the task of designing a toy that will allow children to make more toys. The VP has fond memories of playing with his creepy-crawler set (described in more detail below) as a child and wants to provide the next generation with such memories. The new product development team has created a concept and built a prototype. The concept is a product that allows children to heat metal until it becomes molten, pour it into a mold, and create a small toy or piece of jewelry in the process. The prototype created by the new product development team is shown in Figure 1.
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The team has identified a metal to be used that comes in pellet form, and has a low melting point. A sample of the metal pellets is shown in Figure 2. The molds of the prototype are a synthetic rubber and are shown with a part in one of the mold halves in Figure 3. Talcum powder is used as a mold release agent to insure that the metal does not bond to the rubber mold
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The two-part rubber mold is mounted, and held in place on a tilting table (roughly outlined by a dashed line in Figure 4). The metal pellets are poured into a small crucible that is held by screws to the same tilting table. A heating element is located directly below the crucible. Once the metal becomes molten the table is tilted so the metal flows into the mold. The table remains tilted until the metal in the mold is cooled. The table can then be tilted back and the cast item removed.
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Figure 4. Parts of the Die Cast Factory
A Brief History of "Hot Stuff' for Kids
In the sixties, one of the first toys that involved forming toys using heat was called Vac-U-Form. It was a toy that heated plastic until it was very soft and pliable. The plastic was flipped off the heater onto a mold and a small vacuum pulled the plastic over the mold. After it cooled the plastic could be cut out and assembled into toys. As you can see from the box the heating element and partially melted plastic are not protected. Burns resulted, but most families at that time understood that minor burns were an "occupational hazard" associated with any such toy.
Shortly after the Vac-U-Form, Mattel released a product called "Creepy Crawlers." This product allowed children to pour plastic "goop" into metal molds that were baked on a specially designed hot plate. A cooling tray filled with water was used to cool the mold and allow nearly immediate removal of the toy from the mold.
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The Creepy Crawler Product is similar to the Vac-U-Form in that safeguards against children burning themselves are minimal. The temperatures used on these devices generally cause first-degree burns but could, in the worst cases, cause second-degree burns.
Product Design Issues
Concerns from corporate legal department suggest that how consumers and the public respond to children burning themselves will not parallel the experiences of the 1960's. During the intervening 40 years, corporations have seen a rising propensity among consumers to litigate when injuries result from the use of products. This is true even when the customer makes a mistake using the product. Furthermore the burns resulting from molten metal will be worse than for previous products which used plastics. The injuries that result from direct contact with molten metal will certainly be second degree and possibly third degree burns.
The marketing department's representative on the design team has concerns that the product will not sell effectively if it costs more that $35. Design changes that enhance safety but drive cost significantly higher will negatively impact the profitability of the product.
If the product is to be approved by the legal department, efforts must be made to insure the product can only be used properly and safely. If a child is injured it must be the result of clear, demonstrable efforts to circumvent safety features that are inherent in the product. However, all these features cannot have a significant impact on per unit cost
The New product design team must now enhance their current design (as represented by the prototype) to meet these additional product requirements. Determine what mistake-proofing features are necessary for this product to avoid undue product liability and suggest ways of accomplishing this mistake-proofing at minimal cost.