High-Speed Machines Deliver Speed, Accuracy, Repeatability and Finish
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.
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.”
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.
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.”
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.”
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.”
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.”
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