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When Mark Kite founded Dura
Mold (Stevensville, MI) a
little over two years ago with 20 employees, he had no idea how quickly the company would take off and grow to 39 employees. They quickly discovered that diversification was a key strategy in the company’s growth and stability. Also key was finding the proper high-speed machining technology to handle the company’s widely varied needs. Today, Dura Mold builds plastic injection molds, zinc and aluminum die cast dies, and prototype tooling for industries including automotive, appliances, lighting, home and office furnishings, and recreational vehicles.
Mold cavities like these, manufactured by Dura Mold, form transfer plates for automatic transmissions used in many cars today. The complexity is obvious, with over 1,000 CMM inspection points to tolerances of 0.0010” or less. Images courtesy of Creative Evolution.
According to Kite, price and delivery are always big challenges. “We are constantly racing to get our customer and their product to the market before someone else does and still produce it at a price that is competitive in the world market,” he states. “However, we also face the challenges in a lot of cases to help our customers develop parts that are moldable or castable and functionally serving the end user. Many times we work with the customer to alter the geometry of the part to improve the flow of material into difficult-to-fill areas or redesign the part to improve release of the part from the tool. Also, we cannot afford to be reworking the same piece of steel because it does not meet either customer requirements or for making things fit at final tool assembly. It is very important that we get it right the first time.”
That is just one of the many reasons why Dura-Mold chose high-speed machining centers manufactured by Creative Evolution (Schaumburg, IL). “We looked at our most time-consuming part of the tool and worked on it first,” Kite explains. “That is the cavity detail itself. We needed to make it as fast as possible and run unattended as much as possible.”
Kite found that Creative Evolution’s machines were among the “best controls” available. “They have been proven to make the most efficient use of the motion to get the job done,” he states. “Their personnel have been in the business of writing machine codes since the time CNC machines were introduced. Also, they have one of the most economically priced machines available, but still use high quality components.”
Accuracy Counts
Of course, speed and unattended machining mean nothing if accuracy is not maintained. “Accuracy is a very key element in our tooling,” Kite points out. “Recently, we built a two-cavity tool that in layout had more than 1,000 CMM checks on each part. On the first sample of that tool we had zero dimensions that were out of tolerance. We are consistently working to be within 0.0010" on part shape, locations, sizes and shutoffs.” Dura Mold Vice President Frank Bock adds that tolerances range from 0.0002" to 0.0015"—depending on the job.
Dura Mold Vice President Frank Bock (left) and CNC Supervisor Craig Naumann (right) are in front of their latest Creative Evolution HSD-500 machine. A transfer plate in process can be seen on the machine’s table between them.
According to CNC Supervisor Craig Naumann, the company always shoots for 0.0001" on everything, especially electrodes. “Accuracy and uniformity makes every other step after milling easier,” he explains. “For example, the EDM runs more efficiently and makes better cavities when the electrodes are not only accurate, but also consistent.”
Unfortunately, the machines the company had on the floor initially were not meeting their needs. “Dura Mold was experiencing reliability issues on their older machines,” notes Todd Schuett, Creative Evolution VP and sales manager. “The challenge of keeping costs down to compete is ongoing so there is a temptation to run older equipment. Time has proven that Dura Mold’s investment in Creative Evolution has given them a competitive advantage in the unique blend of reasonable/modest cost, with high performance on par with other prestigious machines. There is so much pressure to buy machines twice the price, an investment equal to or greater than the value of many entire small businesses. The Creative Evolution CNC provides those same capabilities for a lot less money, yet delivers on the promise.”
Dura Mold has purchased three Creative Evolution high-speed machines over the past two and a half years: two model HSD-500 with 20" x 16" x 16" travels and 30,000 rpm spindle, and one HSD-1400 with 53" x 28" x 26" travels and a 24,000-rpm spindle. “The two HSD-500s do small and intricate work and very fine finishing,” Bock explains. “The HSD-1400 is much bigger and stronger. It can use larger cutters to rough parts faster. While it is not quite as quick or agile as the smaller machines, it gives us the size capacity that we need.”
The “Evolution” of a Machine
According to Creative Evolution Vice President and Sales Manager Todd Schuett, when first conceived in 1992, the Creative Evolution CNC was designed to offer four key advantages:
- A new high level of high performance for complex three-, four- and five-axis contours from CAD/CAM.
- Built-in networking support to obsolete DNC systems.
- Open systems architecture to avoid proprietary parts and enable clients to have choices in service.
- Update-ability by software, to make new features available for a modest software charge instead of requiring replacement as is customary to the industry.
One key feature that attracted Dura Mold to this CNC is the look-ahead feature. “In essence, the control is constantly analyzing the geometry ahead so that it can accurately reproduce the desired shape, yet slow down only as much as needed to achieve that goal,” Schuett states. “While many companies have implemented various degrees of look-ahead, we continually refine our CNC to be better than any. It is unique in that it does not look ahead either a constant number of blocks or a constant distance. The look-ahead is dynamic to constantly analyze a changing amount of data depending upon the geometry being cut and the individual machine’s performance. The very latest in high-performance hardware and low-level computer logic help us maintain that advantage.
Another key to performance is customized tuning of each machine on-site at client locations,” Schuett continues. “Variations in foundation, power, and even microscopic variations in the machines themselves can have an impact on performance. This CNC is individually tuned to maximize its performance so that it smoothly achieves each commanded position in a program without excessively stressing or straining any component of the machine system. The on-site optimization doesn’t stop there, but is topped off with on-site laser calibration. The result is a machine that moves quickly and confidently through its programs, and owners and operators that confidently work to a new level of speed and precision.” |
Need for Speed
“The performance of the machines speaks for itself,” Bock affirms. “The speed, accuracy, repeatability and finish have given us a lot of confidence in the product. One example is that we basically ‘jig grind’ holes on the Creative Evolution CNCs with cutters. Spinning the holes on the locations with cutters is accurate, makes good looking holes, and is much faster. This is a huge advantage.”
According to Naumann, the HSD-1400’s major plus is that it combines large size with a fast and powerful spindle. “It can remove material quite well, but also can handle small cutters effectively with 24,000-rpm maximum speed. We often use this to repair tools or make engineering changes without disassembly, because the machine can handle the entire mold assembly in many cases. This saves a huge amount of time.”
Better Business
Since implementing these machines on the shop floor, Dura Mold has seen a marked improvement in its molds. “The Creative Evolution machines give us the capability to produce high accuracy and good surface finishes that allow us to be more competitive with pricing on the world market,” Kite affirms. “They also have improved our rework time, polishing time, fitting time and delivery time.”
This close-up view of one area detail on the transfer plate shows the very fine finish produced right off the Creative Evolution CNC. Dura Mold’s clients report longer tool life—due in part to the higher accuracy and fine finish as the part comes off the machine.”
Bock expands on Kite’s sentiments, adding, “We have increased our volume significantly. It helps the profit margin in the end. This is a good thing. At most, it takes us just half the old times to do the work and we are constantly improving on that. The machines have infinite capabilities—they are waiting for a new challenge. We now run unattended because of accuracy and the thermal stability of the machines, and we have no worries about spindle growth. We run 24/7, unattended, even through the weekends.”
Naumann notes that the time to run jobs is unbelievable. “We are ahead on our CNC milling deliveries, so milling is no longer our bottleneck,” he comments. “One major automotive customer reports that their die cast dies are holding up much better, casting more parts and requiring less maintenance and replacement.
A Ringing Endorsement
The employees at Dura Mold couldn’t be happier with the choice they have made. Bock points out that Creative Evolution’s customer service is exemplary. “It’s not always that there’s a machine problem—sometimes it’s us,” he says. “Creative Evolution has been helpful with implementing the new processes for high speed and keeping us running all of the time.” Kite adds that problems are often solved with a phone call, or if the problem warrants, a company representative is at the door within a matter of hours—not days.
Kite advises shops facing similar challenges to get up-to-speed with technology and seek the best value available to get the job done. “Look for something that will be accurate, fast, dependable and easy to keep running,” he states. He adds that Dura Mold’s achievements would not have been possible without his “extraordinary” staff. “Our team has been great at working together and finding solutions. Everyone here has a part in it. We have great employees with great attitudes. Most of the credit for our success must be given to the staff that carries out our vision.”
Transfer Plate Mold Uncovered!
The transfer plate mold shown on the cover makes one of the key components in automatic transmissions for cars. It mounts to the valve body and transfers the transmission fluid from one stage of the transmission to another—thus the name “transfer plate.” Many mold builders will recognize the part, either from having built tools for them or from experience with car repairs.
This transfer plate mold—and many others like it—are made by Dura Mold, Inc. (Stevensville, MI). Dura Mold founder and President Mark Kite says they take pride in helping build a better, more reliable product for their customers by using cutting-edge machinery and techniques. By machining these molds rather than burning them with EDM, Dura Mold’s tools have consistently been accepted at the first inspection, and they reportedly run longer, too. This is a real win-win on all levels, making the tools more profitable for Dura Mold to build, and more profitable for automobile manufacturers to run.
Bill Anthony, president of RoadMaster Transmission Service, Inc. (Schaumburg, IL), is respected throughout the industry and holds several patents relating to automatic transmission designs. He reports that high accuracy is essential to transmission function and reliability. “The transfer plate controls what gear the transmission engages,” Anthony says. “Any deviations in the transfer plate can result in fluid being transferred incorrectly, essentially causing a leak into the wrong chamber. That can cause the transmission to shift incorrectly or even engage two gears at once. Imagine the potential catastrophe for the unfortunate driver of that car! Transfer plates must be extremely accurate.”
Most tool- and moldmakers shake their heads when they look at the complexity of parts like this. The staff at Dura Mold embraces the challenge. “This kind of stuff makes the moldmaking industry an exciting place to be today,” says Kite. “It’s nice to watch the excitement in the employees’ eyes when we give them the technology.” |
Total Solutions
One of the keys to Dura Mold Inc.’s success with high speed was in their initial training. The machine was sold as a package with the tools for success, including on-site training on Dura Mold’s own work. “Before we installed the first HSD-500, our fastest spindle was 8,000 rpm, and we normally worked with feedrates around 40 ipm,” says CNC Supervisor Craig Naumann. “Not only did Creative Evolution install and set up the machine, but they also coordinated additional training with a product specialist from OSG Tap & Die (Escondido, CA).”
Just days after the machine order was placed, OSG’s Brant Pascavis met with the programmers at Dura Mold to discuss the new high speed techniques for milling their first transfer plate. “Brant loaded our IGES file into his own computer and worked with us on the toolpathing strategy,” recalls President Mark Kite. “He picked out cutters with us and helped plan the entire process. At the end of the first meeting, we had scheduled the startup and first test cuts. Both suppliers helped us to hit the ground running with high speed.”
“We pride ourselves in offering total solutions to get our clients properly outfitted for their own work,” says Creative Evolution Vice President Todd Schuett. “Although we have worked with high-speed milling for more than 15 years, it is still new to many in the industry. Our experience and individualized approach can make it much more affordable, yet we go the extra mile to stack our customers’ odds for success. We evaluate their needs and make recommendations for dust collection, fixturing and workholding (like magnets, pallets and robotics), toolholders and shrink systems, and even the cutters themselves. While we would like to have all the answers, we find it best to work with industry specialists like at OSG.
“We really count on OSG,” Schuett continues. “They serve as an extension to our company with special expertise—not only in cutters—but the latest in high-speed techniques. There are many great cutters in the marketplace today. OSG’s special asset is a depth of technical expertise in the field. Brant Pascavis is just one example. Before working for OSG, he worked for more than 10 years in a mold company in Cedar Springs, MI. He is just one of OSG’s excellent engineering resources, and their accessibility to our customers is critical to those clients’ success.”
Thomas Edison is widely known for his claim that his success was 1 percent inspiration and 99 percent perspiration. Buying the equipment is part of the process, but the real work begins when the machine hits the floor. “Our partnership with Creative Evolution and OSG helped make our implementation a lot easier in large part because of the personalized training,” says Kite. |
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CASESTUDY:MACHINING
