.Thinking the problem is on their end, they try every possibility to access the file before finally telephoning Milacron. "Milacron uses Parametric Technologies Pro-Engineering (Pro-E) in silicon graphics, and we use Computervision CADDS5 on Sun workstations," explained manufacturing/CAM engineer Rob Atkinson. "They had written the tape in SGI specific format, which Sun can't read. When we called them, they realized the mistake, and sent us the right format the next morningÑ24 hours behind schedule."
"We were pretty frustrated," Magee said, "but we knew we could still get it done. You see, we were pretty familiar with LOM, and had done some calculations on how many layers and how much processing the pattern would take on our competitor's machine. We already knew how long it would take us to cut the wood."
Making Up Time
8 a.m., Friday- The CAD data finally arrives, and Atkinson, along with his part- ner Steve Hutchison, set to work. "We con- verted the IGES file from Pro E into CADDS5 format," Atkinson said. "At that point it was just a surface model from Pro-E. I modeled the cope and Steve modeled the drag."
The work continues all day Friday, and for several hours on Saturday, with Atkinson generating NC tool paths while Hutchison completes the 3-D model. Gating is designed and molding requirements are laid out. "When we finally did get the file, it was a good model with trimmed surfaces, which speeds things up a lot," Atkinson said. "We generated our own solids using their geometries, added draft, shrink and the parting line. We then defined work-piece size and generated tool paths. I didn't even dimension anything, just went ahead and made the cuts and it turned out to be dead on."
In the meantime, the wood that will be machined to form the pattern has been glued together so as to be ready to go when the model is complete. All tooling for the casting, including the corebox, will be done on the router out of maple and poplar hardwood selected for its easy-to-machine grain structure.
9 a.m., Monday- Atkinson delivers the completed file to the pattern shop, hav- ing written a post that allows the router to cut in millimeters, rather than the standard inches. Cutting begins immediately, and will take 10 hr of mostly three axis machining, using standard end mills with a high-speed, 12-hp router with 3/4 in. tin coated tooling. It is machined at 8-12,000 RPM with a feed rate of 140 in. permin. "We went 0.0005 in. over so there'd be little sanding involved," Magee recalled. "We could just put a coat of paint on it and mount it." The pattern is finished with a 0.001 scallop. Though they have the option to save time by leaving the pattern loose, Cast-Fab's team elects to mount it.
8 a.m., Tuesday- The pattern is painted. Once dry, it is mounted to run in the foundry.
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The Final Leg
9 a.m., Tuesday- Medium Molding Manager and 33-year foundry veteran Jim Garrison hand carries the mounted pattern to the molding department. With the corebox having been completed first, the casting's small "S" core is already made and awaits the mold. The pattern is run in the semi-automatic furan nobake mold machine and a single mold is produced. "Since the mold was flaskless, we made sure we had a good, heavy closedown and that it was weighted properly," Garrison said. "It was such a small pattern, it really didn't require a lot of special handling. The key was just staying on top of it, paying attention to the details and making sure it was done right."
10 a.m., Tuesday- The completed mold is ticketed and grouped on the pour- ing floor with other molds to be filled from the same chemistry gray iron heat.
2 a.m., Wednesday- The mold is poured and left to solidify.
6 a.m., Wednesday- The cooled and solidified casting is shaken out. Irv White, casting cleaning manager, races the part through cutoff, grinding and blasting. "It went through our depart- ment in a couple of hours," White said. "Under normal circumstances, it would probably take a day, but we jumped it over some other castings." Before head- ing to the shipping department the casting is submitted to the only layout check that can be performedÑverifying six dimensions off a sketch made from Cast-Fab's 3-D model. The dimensions check out and the shipping department rushes the casting to the customer.
2 p.m., Wednesday- The part is deliv- ered to Milacron, only 8 hr after shakeout, 12 hr after pouring, and four working days after the file was received.
Savoring Victory
Cast-Fab's accomplishment was remarkable; while Milacron officials had the finished part in their hands Wednesday morning, the competition hadn't even begun to create its pattern. Milacron received the other foundry's finished part on the morning of the 24thÑstill only seven working days after the competition began. That foundry also provided Milacron with a flow analysis and a completed Pro-E file of the part. "If we'd have gone about this the normal way," Martin said, "it would have taken at least seven weeks."
The foundry's 5-axis router had performed beautifully. "A lot of it had to do with the part, which was perfect for the router," Magee said. "We had the apparatus in place to handle it when it came in. The part probably wasn't suited to LOM, which might be better for a different type of casting. I think the big benefit for Milacron was learning how to apply the right technology to the right application, the right part."
Martin agreed. "We got to test a lot of technology, find out what it could do, and find out what two of our suppliers could do. You can't apply these technologies everywhere, they do have their constraints, but like any new technology, they'll only get better." The contest furnished Milacron with the comparative information it was looking for, and Cook felt that the project reflected the Wolfpack philosophy. "Patternmaking is an old skill," he said, "and it has a lot of paradigms that probably need to be broken."
Beyond technology or process improvement, Cast-Fab's victory had much to do with its people. "They put together a first class team over there," Martin said. The foundry is rightly proud of that team. "The neatest thing about it," Magee said, "was the way the project moved from department to department and when the time came, everybody did their partÑjust took care of it. It was a great example of teamwork."
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