In 1995, Melling Tool was trying to unload an expensive three-axis vertical machining center with an unreliable and out-of-date control for $13,000and there were no takers. The ten-year old VMC still had good iron and could still make high quality parts, but control problems made it usable only 20% of the time. Today, thanks to a new CNC control, not only has the VMC's performance improved, but Melling discovered a money-saving way to expand manufacturing capacity.
The new CNC control is OpenCNC®, the industry's only production-proven, software-based CNC machine tool control. Developed by Manufacturing Data Systems, Inc. (MDSI) of Ann Arbor, Michigan, OpenCNC requires no proprietary hardware or motion control cards. The entire control is on a disk. Control replacement with OpenCNC not only promises to save manufacturers money by extending the productive life of their machine tools, at Melling it actually improved the VMC's performance over the original. But most significantly, OpenCNC also opened up a world of possibilities for Melling to grow its business, by allowing the company to expand into new markets without a lot of additional expenses.
Finally, A Way Out of a Dead End
Melling's dilemma with its machining center was threefold: it used an obsolete Heidenhain proprietary control that required operators to master a hard-to-use programming language, and the learning curve was steep. There were also limitations as to what could be programmed on the machine. And, after a few years, downtimes increased until the machine was only usable about 20% of the time.
"Nobody wanted to use it," recalled Tom Foster, CNC Mill Department supervisor for Melling. "It was our weak link."
Melling found itself at the same dead end that manufacturers have confronted for years: how to salvage a still-viable machine tool with an obsolete control, without spending more than the hardware was worth. They considered selling, but after dropping the price to $13,000, there were still no buyers. They also considered changing the control on the machine to another traditional "black box" proprietary control vendor, Foster recalled.
"The new vendor quoted us $35,000," he said, "plus another $5,000 for our time and materials. When you're talking about a machine you've been trying to get rid of for $13,000, it doesn't make sense to put $40,000 into it."
The Solution Sounded Too Good to Be True
Melling heard about OpenCNC's impressive results at a neighboring factory, Great Lakes Industries of Jackson, Michigan. At Great Lakes, 15 machine tools were retrofitted with the OpenCNC software, including lathes, machining centers and gear hobs. As a result of switching to OpenCNC, Great Lakes doubled their capacity and reduced downtimes to zero-at a fraction of the cost of using traditional proprietary control solutions.
"We were skeptical that anything could be as good as OpenCNC seemed to be," confessed Dave Horthrop, president of Melling Manufacturing Group, a group of subsidiaries that produces a variety of parts, fittings and assemblies for the aerospace, automotive, medical, and prototype/tooling industries. "Instead, it has turned out to be much better than we even hoped."
Control Replacement was Easy
OpenCNC took to the VMC as smoothly as Mellings employees took to OpenCNC. They ripped off the old control, installed an office grade PC purchased at CompUSA, and started running parts with OpenCNC in control.
Operators noticed the advantages of a software-based control right away in the lean-and-mean look that OpenCNC gave to their machine: "You can spot a machine with OpenCNC just by looking at the back of the machine tool," Horthrop said. "We were able to get rid of most of the electrical cabinet. Now there's nothing there except a few wires. It's very simple."
And they were impressed that they could still use the drives and motors that were already on the old machineanother way that OpenCNC saves money.
"The retrofit was relatively painless," agreed Foster, who did the retrofit himself in less than two weeks, while also supervising the CNC mill department. "Even though the integration was new for me, it went pretty fast. And because with OpenCNC we were able to use the same programming language we use on all our other machines, it was very easy for the other operators and setup people to run it. It felt like coming home."
Results were Spectacular
The results were impressive: The formerly non-productive machine started to run at full capacity and has continued to do so for almost two years without any problems. Uptime increased from 20% to 100%. And the most dazzling of all: the machine's productivity improved 50%, by using the existing drives and motors more efficiently.
"Before OpenCNC," Foster pointed out, "the maximum rapid rate on the Heidenhain control was 390 inches per minute. After OpenCNC, it's 590 inches per minute. Over a 5000 piece run, that makes a huge difference."
Operators also noticed the improvement. For starters, all the functions they needed were right on one screen, so they didn't have to scroll through several screens to find what they needed. "OpenCNC is a big improvement over the old control," stated Dominic Stepper, CNC mill setup. "The whole thing is better structured. It's nice to work on it now."
Horthrop agreed. "Thanks to OpenCNC, any operator can be assigned to that piece of equipment and operate it very capably. It's as user-friendly a control as we've ever seen. And the dependability and uptime have been virtually 100%. It operates multiple shifts every day, five days a week, without any problems whatsoever."
It was beginning to look more and more like the VMC would be scrapped. Then, OpenCNC appeared.
Compatible with NC Programming Systems
OpenCNC proved to be totally compatible with Melling's NC programming systems-SmartCAM® and MasterCAM®-giving operators DNC capabilities for the first time on the machining center.
OpenCNC's software includes a fully integrated DNC capability that enables the machine tool operator to download part programs when they need them.
Saves Money throughout the Life Cycle
Because OpenCNC is not dependent on any proprietary hardware or motion control cards, it saves money throughout its life cycleunlike traditional controls.
"If you need a replacement board for a proprietary control, it's only available through that company and generally they're very expensive," Foster said. "With OpenCNC, replacement parts can be bought at more than one place-we can shop around. We can buy a PC at any local discount store we want."
Opening up New Markets
The cost-effectiveness of the OpenCNC control enabled Melling to add new manufacturing capacity at a fraction of the cost of buying new CNC machine tools. This has freed the company to consider new markets that would have otherwise been very price competitive.
"We used to disregard certain used equipment on the market based on the control," Horthrop reports. "But now I'm looking at old stuff with an entirely different attitude. We're currently looking at purchasing equipment for retrofitting to use in a mature market we haven't been in before. Before OpenCNC, it wasn't cost-effective. But when you can retrofit a high-quality old machine tool for a nickel on the dollar, it opens up all kinds of new possibilities."
The Future of CNC Controls is Hereand it's Software
There's no doubt at Melling that the future is here. Dave Horthrop believes OpenCNC will change the manufacturing industry as he knows it in several key ways. "OpenCNC will extend the life machine tools," he says, "and it will allow companies like Melling to compete in new markets at a competitive cost."
But most of all, Horthrop is hoping to see OpenCNC on new machine tools. "If OpenCNC were to become widely available on new machine tools," he says, "it would be of tremendous interest to us. To have a control that you can maintain yourself and upgrade as easily as you do any other software-this will be the way, I believe, that everyone will want to go."