Almost every longstanding shop has had a machine like this - good iron but the controller is shot. The difference is that Melling Manufacturing Group in Jackson, Michigan, was able to bring their vertical machining center back to life. And it didn't take an expensive maintenance program. All it took was replacing the old hardware-based CNC with a software-based system, running on a mail-order personal computer. This PC control not only resurrected the machine tool, but it also lets the machine run better than it ever did with the old controller.The way it was, the most we could get for that VMC as a trade-in was its scrap value," said Melling President Dave Horthrop. This 45-man shop had owned the machine since 1985, and relied on it for years. But over time, the control unit had experienced its share of problems, with downtime getting longer and longer and repair bills going higher and higher.

Even when it was running, the machine was very difficult to program. The proprietary control was badly out-dated and no longer supported by the builder.

"Eventually it got to the point where, at best, we could use it only as a programmable drill press. Even at that, our machinists avoided using this machine as much as possible - most of the time it just took up valuable floor space," Mr. Horthrop recalls.