January 2008 Edition

THE LAST WORD

Advanced CNC Isn't a Luxury; It's a Necessity

For companies to keep up with competition, they need the latest and greatest machines

The short list of musts for machine control used to contain the basics of axis motion, table motion, spindle control, and tool change. As part complexity and cost pressures increase, the method by which part designs are fed to the machine have changed. Now, more is required of the shop in the areas of cost containment and performance validation.

For controls suppliers, it has become a matter of keeping pace with both motion control and process control to help machine builder customers – and ultimately the end user shops of all sizes – better accommodate growing challenges. The how of accomplishing these tasks will set the stage for the future.

Value-Added Demand

Job shop and contract manufacturer markets in the past could prosper with a core of good customers and a steady flow of work. But, the trend changed to more outsourcing, thus starting the demand for value-added services. Requirements are further complicated by new competition, a decline in the available labor pool, and further cost reductions.

Because of this progression, shops that want to survive must raise the bar on performance through several strategies, including the latest machining technology. It's here that the controls supplier can be an asset to a shop's operation: when the machine can do more, the shop can do more.

Improvements in automation and a faster time-to-first-part provide the ability to run more small-batch jobs and squeeze more profit from the larger production runs, resulting in more opportunities for a shop of any size. Forward-looking shops automate, or discover ways to maximize the productivity of high-end machine tools. Either way, keeping up with technology is a necessity.

Maximum Output Checklist

An advanced CNC should have the following capabilities for maximum shop output potential:

• NURBS – non-uniform rational b-splines – the control's ability to machine contours in a way that's superior to the old point-to-point control. NURBS allows for more complex parts and a better finish on 2D surfaces.
• A part verification program which takes the CAD drawing and quickly makes the first part, also reducing the cycle time and scrap material. It "sees" the cutting functions through the post-processing stage to optimize the tool path faster and more effectively.
• More data handling functions to allow access to third-party web sites for material specifications, which the machine then factors into the production cycles in real-time.
• A gathering stream with the ability to accommodate wireless and advanced communications systems, for an efficient and economical means of data transfer.
• Adaptive control that lets the machine make real-time adjustments to the program for greater consistency in the parts produced.
• A more comprehensive library of motion and process control characteristics, letting the advanced CNC accomplish EDM, waterjet, laser, and ultrasonic machining.
• Increased axes of movement that put more power into the machine, making robotic handling, transfer mechanisms, remote tool/workpiece manipulators or storage carousels, rotary tables, and other devices a realistic possibility for any sized shop.

Hard Work, Not Magic

Advancements in CNC technology lower the cost for builders to implement higher levels of control into machines and remain cost-competitive. Looking for those types of machine tools enhance a shop's success. However, this is no magic solution, because a shop must still have the right team to handle sales, programming, machine set-up, production, and quality monitoring/documentation.

If the above features are not on a current machine, consider the possibility of a retrofit upgrade. In doing so, be sure the motor and drive packages complement the CNC onboard. After all, the greatest jockey won't win the race if the horsepower is insufficient.

What do you think?
Will the information in this article increase efficiency or save time, money, or effort? Let us know by e-mail from our website at www.ModernApplicationsNews.com or e-mail the editor at pnofel@nelsonpub.com.