PC-Based CNC Revives Vintage Machines

They just don't build machine tools like they used to, according to Andy Vigé, president of Machine Specialty and Mfg. (Youngsville, LA).

Vigé couldn't find a new machine tool that could take the punishment that one of his 20-year-old Warner & Swasey lathes could. He'd been buying used W&S machines for years, then driving them hard to make pipe pressure fittings and flanges for the oil industry. The iron in them was still good, but the original controls were not. Aging hardware-based CNCs on the lathes had become obsolete, and because they were proprietary, closed systems, the controls were starting to cost the company plenty.

"When a motion board goes on one of these, it takes weeks to repair or replace them," Vigé says. "Frequently, the original control company can't help us at all. When a machine goes down, and you fail to produce 300 - 400 pieces of flange that you would normally sell during the day, you feel it." To top it off, Machine Specialty and its competitors were in the middle of a two-year price war, and the company couldn't afford to lose ground.


Retrofitting its W&S lathes with open-architecture software CNC gave Machine Specialty access to machine data, eliminated purchase of new machines, and helped the company gain control over production and stay competitive, according to president Andy Vigé.

The solution Vigé found was so successful that, 18 months later, he has transformed almost every CNC machine he owns and improved production by 30%. And he did it without buying a single new machine.

That solution was OpenCNC software from MDSI (Ann Arbor, MI), an open-architecture CNC package that uses no proprietary hardware or motion control cards. Because it runs on off-the-shelf PCs and Microsoft Windows operating systems, users are not locked into proprietary arrangements for hardware, control repair, or control upgrades.

Vigé credits the package with helping him:

* Reinvigorate his old machine tools
* Gain access to machine data that helps him manage his company
* Avoid having to buy new machines
* Gain control over production
* Stay competitive.

"OpenCNC gave me a jump on everybody I compete against," he says.

Machine Specialty has been in business more than 20 years. With about 75 employees, the company makes pipe flanges and fittings for a variety of oil and gas applications, from deep-water drilling in the Gulf of Mexico to the North Sea, where they perform critical applications such as containing high-corrosion fluids or withstanding pressure of up to 20,000 psi (138 MPa). The business is competitive and global.

As company president and co-owner, Vigé constantly looks for manufacturing solutions to help him optimize profits and resource utilization. Machine downtime costs money--$8500 per day per machine, Vigé estimates. He figured his Warner & Swasey lathes were down about 20% of the time with control problems. When he realized he was spending $2,000 - $3,000 per machine per month to keep the old controls going, plus what it was costing him every time a machine stopped, enough was enough.

Besides upgrading his old machines, Vigé was looking for answers to several manufacturing problems. He wanted to decrease cycle times. He wanted a control that in-house maintenance personnel could service. He wanted to use existing servos and drives. And most of all, he wanted access to data.

"I needed a better tracking system for what was going on with each machine," he says. "How long is the machine running each day? How long does it take to do a batch of parts? How many parts can be done in one day per machine? I can't get this information from traditional controls."

When Vigé heard about OpenCNC, he knew it was what he wanted. "It was software that let me use any drives that I wanted or any PC," he said. "I didn't have to buy a whole package. I could buy the best drives or the best PC I wanted. The MDSI control doesn't care which one you use. It's software, so we can put it into any package we choose."

The first machine retrofitted with the software was a W&S 2 SC lathe. Eldon Richardson, an MDSI integrator out of Meridian, MS, performed the retrofit, which involved pulling all the wiring from the old cabinet, removing the old control, installing OpenCNC on a new PC, rewiring the panel, and programming the machine. The old servos and drives were in good shape, so he left those in place.

Machine Specialty machinist Mike Thibodeaux worked with Richardson to learn about the software. Since that first machine, they have refined the retrofit process so that Thibodeaux and other Machine Specialty employees strip out the old control and remove all the wiring. At his shop, Richardson builds a bolt-on case for the monitor and PC, loads the OpenCNC onto the PC, and programs it. He then takes the completed package back to Machine Specialty, where he re-wires the machine and puts the new control in place.

Richardson says the process goes quickly if existing servos and drives are kept, which is what Machine Specialty chose to do on most of its machines. "The first machine took about two weeks," he says. "Now, it's much faster. We have actually taken four machines down at the same time, retrofitted them with OpenCNC, and had all four of them up and cutting parts in just eight days."

Thibodeaux found working with the software CNC easy. "It's not at all difficult, and I'd never done it before," he said. "If there's a problem, you can see what it is on the screen. Before OpenCNC, I'd never programmed a machine before. Now I'm so busy programming I don't have time to help wire."

Andy Vigé feels his company gained a competitive edge with OpenCNC, and he continues to add machines to his retrofit list. He now has more than 25 machines running with the software--almost his entire CNC machine inventory. Vigé says the MDSI control has improved Machine Specialty's processes and profits by allowing access to better information on the manufacturing process.

"We have setup guys walk the floor every morning to check the previous day's work," Vigé says. "They now pull data from the machines and give me daily production reports. I can give operators quotas per hour. It has helped me realize what should be done per day on each machine, no matter who is running it.

"Also, I figure I'm getting a 30% increase in production," he adds. "From six parts per hour per lathe, we're now up to eight per hour." Other benefits he cites include improved workpiece surface finishes resulting from optimized spindle speeds and smoother toolpaths, relatively easy operator training, flexibility to purchase control packages and components the way he wants, and reduced overhead and personnel costs.

With almost all of its CNC machines using the software CNC package, Machine Specialty is busy and profitable. The company could network all the machines, then monitor all of them from a PC in Vigé's office or from home. Networking, plus the machine data accessible from the MDSI control, opens the door to Internet-enabled manufacturing. First, however, plans are underway for Machine Specialty to retrofit more machines with OpenCNC.






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