Chips Really Fly At Aerospace Subcontractor

After a decade of mergers between aerospace companies such as Boeing and McDonnell Douglas, Lockheed-Martin, and Northrop-Grumman, the industry has gone through some rather significant changes. Among these are down-sizing of their work force and the trend to subcontract much of their manufacturing work, especially to machine shops with five-axis machine tools. At the same time, these companies have trimmed their supplier list to include only their most dependable suppliers. With the recent surge in commercial aircraft orders and the continuation of major defense programs, the demand on these suppliers have never been greater. In some cases, lot sizes have become smaller, requiring suppliers to be more flexible. In other cases, assemblies are being replaced by a single part, increasing the need for more complex machining. Of course, the aerospace companies want lower prices and higher quality. However, a very positive note is that they are offering multi-year contracts.

Within the group of suppliers who manufacture complex structural parts is High Tech West, Inc. (H.T.W.Inc.) located in Long Beach, California. The company was started in 1984 by Dal and Tom Rogers as a 5-axis airframe machining house, specializing in the capability to machine complex contoured parts. The growth that aerospace suppliers are experiencing is reflexted by the H.T.W., Inc.’s recent move into a new facility that quadrupled the size of their former quarters. In order to meet the ever increasing demands of the industry, everything is state-of-the-art, including inspection devices, CNC software, and of course machine tools.

NEW VIPER VMC-2100

A recent machine addition is a case in point. The company acquired a VIPER VMC-2100 from Mighty USA, Inc. According to Tom Rogers, the new machine fills a niche that other manufacturers did not offer- a heavy duty VMC with 81″ x 42″ travel. The machine is being used to machine aluminum and titanium, especially on ‘hogging’ operations on large slabs of aluminum. Tom stated, ‘VIPER is really solid with its heavy duty Meehanite casting. We’re using a 2″ diameter, 2-flute, M4 end mill to machine over 1,000 pounds off a 1,300 pound, 5″ slab and there is no evidence of vibration or chatter. The depth of cut is 1.25″ at 3200rpm, and the feed rate is 60 ipm. The part finish clearly shows how solid the machine is.’

In addition to the frame, the VMC-2100 uses large ballscrew assemblies for maximum rigidity and precision. The ballscrews are located in the exact center of each axis, which effectively eliminates heat and lost motion. High torque AC servo units are directly coupled to the ballscrews, moving the axes faster and with more precision. Equipped with ‘state-of-the-art’ Mitsubishi AC digital motors, cutting time is minimized with the high reliability, speed and precision feed movement.

CONTROL SYSTEM FITS INTO THE SCHEME OF THINGS

The VIPER VMC-2100 features a Mitsubishi Meldas 530 CNC 3D graphic control system with a 32-bit CPU. With its multi-window capability, the control mobilizes user-friendly interfacing. This is important as High Tech West has brought aboard several software programs to improve shop performance and all computers are setup to interface with one another.

Most projects arrived on IGES files and NC programs developed with MATRA Sabre multi-axes system with post processor. ProComm is used to transfer NC programs. Software for quality assurance is Geopack and Scan Pack.

Of course the purpose of state-of-the-art machines, like the new VIPER, and various software programs is to improve ‘cut time’ -the time a machine is actually cutting parts. The more productive your machine tool, the more profitable the business. With the demands in the aerospace business ever tightening, machine efficiency is the key to successful business.

By Tom Walsh