Ultra Wheel Co. specializes in producing custom wheels for cars, trucks, and SUV’s. In business for nearly 20 years, all the wheels are manufactured in the company’s 350 employee 6.5 acre plant in Buena Park, California. With wheels varying in size from 14 to 24 inches and more than 50 different styles to choose from, Ultra Wheel Co. offers a wide product line and superior quality at a resonable cost.
All design and machining is done in house and they have refined their processes to the point where new wheels can be designed, produced, and delivered to sales outlets within 30 days. At this level of efficiency, many manufacturers would be content. However, Ultra Wheel Co. prides itself in delivering new products to market quickly, and Ultra’s engineers continually live up to the company motto “quality through technology” by employing the latest manufacturing methods and utilizing state-of-the-art tooling and equipment. “The management of Ultra Wheel Co. has always been very open to new technologies and processes that will further push the envelope of our production capabilities,” says Steve Hetrick, CNC programmer.
It was with this mindset that Hetrick went to WESTEC to look at VERICUT® NC verification software from CGTech (Irvine, CA). “We did have some problems with NC programs. Not long before the show we gouged a mold, which prompted me to look into alternate means of verification. The verify package I was suing at the time showed no problems in the verification, but the part was damaged. I got a postcard from CGTech, and made it a point to check out the software. When we got VERICUT, the program that caused the gouge was the first file I tested to see if it would catch what my old software wouldn’t…and it did. If I was using VERICUT at the time I would’ve caught the problem, and had a chance to fix it before it damaged the part.”
But part verification turned out to be a side benefit to the real money maker: NC program optimization. “We had very good turnaround time, but no-matter how efficient an operation may be, there is always room for improvement,” says Hetrick. But improving efficiency can be easier said than done, especially when you’ve already eliminated the problem areas. The trick is finding the places where there isn’t necessarily a problem in the process, but opportunity to weed out inefficiency. When time is limited and resources are streched, one of the best places to start is at the NC tool path. Hetrick alone is responsible for wheel mold-shop programming, and other miscellaneous programming jobs that range from prototype wheel models, to racecar parts for the owners NASCAR Truck and Winston Cup race teams. The jobs run on Supermax/Max-3 Rebel, Supermax/Max-4, Supermax/Max-1 Rebel, Haas/VF-3, Haas/VF-5, and a Haas/VF-6 machines.
They decided to implement OptiPath®, the NC program optimization module of VERICUT software. OptiPath is a knowledge-based machining package that essentially adds intelligence to the cutter. During the simulation, VERICUT learns the exact depth, width, and angle of each cut. The software also knows the exact shape of the in-process material during each and every second of the entire machining operation. And it knows exactly how much material is removed by each cut segment.
With this unique knowledge set, the OptiPath module determines the best feed rate for each cutting condition encountered, taking into account volume of material removed, chip load, and accel/decel control. Where necessary, the software can also divide cuts into smaller segments and vary the feed rates accordingly in order to maintain a consistent chip load or volume removal rate. It then creates a new tool path, with the same trajectory as the original, but with improved feed rates. “The application of the software seemed very practical for our situation,” says Hetrick. “And the software has exceeded our initial expectations.”
The first job they optimized was a wheel mold machined from hardened steel (38-42 HRC) and cut using carbide inserted end mills. After letting the software analyze the tool path and insert more appropriate feed rates they could immediately tell the difference. “The tool load sounded a lot more consistent,” says Hetrick, “and the surface finish was often better, even with the increased feed rates.” But the real surprise was in how much more efficiently the part ran – cutting 150 minutes from a program that, otherwise would have taken 467 minutes – a 32% savings.
Reaction from the machinists on the shop floor has been enthusiastic. “There is a definite peace-of-mind now. Prior to using VERICUT, machine operators would always have to keep an ear open, listening for the tool to break, or for whatever else might happen. Since we’ve been using the software, and everyone is convinced of the reliability and consistency of the product, machine operators can now start a program, and go work on other tasks in the shop, knowing that the software is looking out for the ‘hard parts’ and adjusting the feeds accordingly.”
Machinists at Ultra Wheel Co. have also noticed other benefits from the software. Tool life has increased. “I used to have to break-up my programs to allow for tool changes. Now I can run much larger programs, and the tools don’t wear-out near as fast.” And although he hasn’t noticed any less wear on the machines themselves, “if prolonged tool life is any indication as to how much less stress is being transmitted to the machine, than I would say there is definitely less wear and tear on the machine.” Surface quality has also improved significantly in most cases.
But the bottom line is in the bottom line. And how much more profitable is Ultra Wheel Co. as a result? “The software has already paid for itself. For example, I documented the job we just pulled off the machine. We took 34.62% off the machining time, and increased the profit margin by more than $1,300 on that part,” says Hetrick. “Management is very impressed. Not so much at the tooling savings, or lack of machine wear and tear, but more so with the quicker build times we are seeing on our molds.”
They were also somewhat surprised to find that their biggest timesavings occurred on finishing operations. “On average, I’m cutting 30% to 40% out of all my finishing times. Keep in mind that finishing is about two-thirds of the overall mill time. 1/4″ and 1/8″ ball end-mills that used to run at 60 ipm, (and the operator would usually override down to 40 ipm on the hard parts) now run between 40 ipm, and 130 ipm, usually staying somewhere between 90 and 130 ipm. I recently finished a typical mold, which I had to run 5/8″, 1/2″, 1/4″, and 1/8″ ball end-mills. A mold similar to this without OptiPath probably would have been on the mill a week, to a week-and-a-half. This mold ran in a little less than 4 days! That’s pretty much the scenario I’m seeing on everything I do.”