Figure CS-33 shows a 5|in. diameter flywheel for use in a large, commercial-grade high-speed computer printer. The part is 3| in. thick to provide a total weight of approximately 12 lb, assuming fabrication from a ferrous-based metal. The only mechanical requirement is a Rockwell B hardness equal to or greater than 50. The most restrictive requirement appears to be dimensional precision, since tooth, bore, hub and diameter dimensions must all be within 0.001 in. of specifications.
1. Based on the size and shape of the product, what are some possible means of producing the part using a rapid prototyping process? Would you make the prototype out of metal or plastic? Would you need to machine the prototype?
2. What are some possible ways to produce this part, assuming that a ferrous material will be used? Select an appropriate material for each of the alternatives discussed. (Note: Casting alloys should be matched with casting processes, high machinability alloys would be favored for cutting applications, etc.)
Which of the above alternatives do you feel would be the "best" solution to the problem? Why? For this system, outline the specific steps that would be necessary to produce the part from reasonable starting material.
For your proposed solution in part 2, would any additional heat treatment or surface treatment be required? If so, what would you recommend?