“Perfection is a goal every business strives for, but when it’s part of your name, you feel even more responsible for it,” says Scott Gauerke, owner/president of Perfect Patterns, an Appleton, Wisconsin-based manufacturer of patterns and permanent molds for a number of industries, including automotive, light commercial and agricultural.
“Of course, we are always striving for better outcomes, reduced costs and most importantly, customer satisfaction,” Mr. Gauerke emphasizes. “We have a great asset in our talented, highly productive employees. We look for the same qualities in our suppliers.”
Walter USA, Inc. (Waukesha, Wisconsin) has become an important partner in helping the 51-year-old business fulfill those objectives. The challenge Perfect Patterns faced is typical of a fast-paced engineering environment.
“We needed to speed up the process we use in our roughing operations to remain competitive and save costs,” Mr. Gauerke explains.
At issue was a pattern intended for use in the foundry industry. Made of 304 stainless steel, the pattern was being produced on a CNC vertical machining center. Paul Ludke, Tool Crib manager at Perfect Patterns, conveys the tall order the company faced: “We needed to prolong tool life, lower tooling costs and expedite roughing and processing,” he explains. “Smoother surfaces and higher spindle speeds to help cut roughing operation times needed to be achieved, as did less breakage to reduce tool and insert change-outs.”
Doug Krueger, Walter’s senior sales engineer, stepped in at this point to offer potential solutions. A strategic meeting between Mr. Krueger, Mr. Ludke and Don Sievers, Perfect Pattern’s general foreman, outlined the company’s goal of increasing productivity in the roughing operations, thus enabling the company to run the finishing operation via its computerized processing at night. The logic was that this course of action would yield a higher quality pattern.
Mr. Krueger recommended Walter’s 3-inch diameter F2330 cutter. By mounting it on the existing Walter NCT modular system, the setup would theoretically be flexible enough to machine the pattern’s shapes, contours and profiles.
The company says implementing the cutter proved to be the right choice. In addition to increasing feed rates by 87 percent, the new cutter facilitated 20 percent faster speeds. Insert life was also improved by 100 percent. Perfect Pattern adds that the cutter also ran more smoothly and quietly when profiling the internal pockets, the inside and outside contours of the pattern.
“We were able to rough one and a half pieces a day at 112 ipm using the P26335-R25 WAP35 inserts,” says Mr. Ludke. “Previously, they had run at 60 ipm. Speeds were increased 20 percent, and piece production time has gone from eight pieces every 2 weeks to eight pieces in 1 week. Now all roughing operations are completed throughout the day, so we can count on finishing operations occurring at night,” he adds.
A second application used the same 3-inch diameter F2330 cutter, running on a large A36 steel chair mold. The existing cutting parameters for the roughing operations were optimized for the new technology, and speed was increased from 470 sfm to 786 sfm—a 67 percent increase. The company also observed a notable improvement in feed rates. Formerly 150 ipm, the feed rates now stood at 280 ipm—an 87 percent increase. In addition, the depth of cut increased by 50 percent.
Perfect Patterns also reports a 61 percent reduction in cycle times—from 280 minutes to 110 minutes. The original inserts required three indexes. With the P26335–R25 WAP35, however, one cutting edge roughed the complete mold. The company is expanding on the success of the F2330 cutter: face mills with 2-inch diameters, along with screw-fit end mills with 1-inch and 1.5-inch diameters, are being integrated into roughing and semi-finishing applications.
The success of F2330 combined with the flexibility of the NCT modular system and all of its components—including adapters, extensions, reducers, milling adaptors and cutting tools—have made all the difference. Executing cutting operations more quickly with increased rigidity means that true contours and smoother cuts (particularly in corners or small radius holes) are therefore achieved, says the company.
The screw-fit system holds the cutting tools more accurately—radially and axially—resulting in increased insert life, says the manufacturer. The system’s flexibility is also said to afford the customer the capability of changing tools, or changing over to a different cutting tool with relative ease.
“Instead of swapping out entire tools, we can now simply swap out components,” Mr. Ludke says.