Machining Center Meets The Production Needs Of The Aerospace Industry

Metalcraft Technology Inc. has come a long way since it opened in Cedar City, Utah, 11 years ago, making $3 clips used in the fuselages of the McDonnell Douglas MD80 assemblies. Today, Metalcraft is recognized throughout the aerospace industry as one of the foremost manufacturers of complex structural components and integrated assemblies. The company has built thousands of airframe assemblies and details for the top aerospace companies.

Metalcraft provides, in addition to sheet metal, turning and full-service metals processing, a broad range of precision machining for the aerospace industry including CATIA-based CAD/CAM engineering interfaces, full service metals processing capabilities, chemical metal processing and FAA-compliant sub-assembly manufacturing.

The company has always focused on analyzing the aerospace industry and pinpointing the exact areas where manufacturing opportunities will develop. "We're expert in anticipating the new demands and challenges our customers will face and adapting our capabilities and technology to meet them," says Metalcraft founder and president David Grant.

For example, Metalcraft had to quickly move into high speed, five-axis machining when the U.S. Defense Department approached the company in 1998 to machine wing spars for the Lockheed Martin F-16 fighter. The F-16 wing spar work meant that Metalcraft would have to purchase not only a five-axis machine with high speeds, but also one that could handle the size of the complex, monolithic spars. The wing spars, notes Wayne Johnson, vice president of operations, begin as a 400-pound block of 7075 aluminum and are machined out to 80 pounds when finished.

To achieve optimum metal removal for this, Metalcraft chose a five-axis V5-3000 vertical machining center from Cincinnati Machine (Cincinnati, Ohio). Mr. Johnson visited manufacturers and studied more than 30 five-axis machining centers. At the end of 6 months, he said, he had narrowed his choices to three machines, based on three key factors: price, dependability and reputation.

What sold Mr. Johnson on the V5-3000 was its twin-axis, tilt head with a full ±40-degree range in A (forward and back) and B (side-to-side) axes, because it is the most advanced and proven head on the market, he says. "First, its range is 10 degrees greater than its competitors. Second, a lot of machine tool manufacturers are just starting to make five-axis machines and are having many problems with leaking heads and breaking seals. In my research, I found that Cincinnati's five-axis machines had the most reliable reputation."

The V5-3000 is said to be perfect for machining the F-16 wing spars, Mr. Johnson says, because its massive 130 by 30.1 inch (3,302 by 765 mm) worktable rides on four sturdy, widely spaced Y-axis linear ways that support more than 2 tons of parts and fixtures. The X-axis travel is a full 120 inches (3,048 mm).

The twin-axis tilt-head is said to provide the rigidity that enables the V5 to optimize the production capability of its 15,000-rpm, HSK-63A spindle, allowing Metalcraft to machine at extremely high speeds and reduce cycle times. The increased stiffness of the 35-hp, S6-60 duty rated spindle allows the V5 to speed through complex part routines with high precision.

The V5 has solidly proven its ability to machine larger, more complex parts faster and at higher quality, Mr. Johnson says, and productivity for parts machined on the V5-3000 has more than doubled. For example, he notes, one part that was being machined in 11 hours on three- and four-axis machines now requires only 4 hours to complete.

"The V5 has done real well for us. We've had no problems with it at all, absolutely no downtime. It's reliable, and it's excellent at holding tolerances. I would not be reluctant to recommend this machine for any company that's looking at five-axis machining," he says.

In fact, the V5's performance led the company to purchase another Cincinnati machine, the U5 five-axis/five-sided machining center, when it gained a contract to machine leading edge skins for the Boeing 737 wing assembly. Mr. Johnson again analyzed the machines that could handle the job and discovered that the U5 was far ahead of the competition in its ability to machine large parts.

Just as the V5-3000 doubled productivity on machined parts, Metalcraft expects the same kind of results with the U5. "With the V5 and the U5, and the experience we've quickly developed in five-axis and five-sided machining, Metalcraft is well positioned to take advantage of any opportunity that develops in the aerospace industry," Mr. Johnson concludes.