Delcam has demonstrated some new developments for machining composite materials using its PowerMILL CAM system for high-speed and five-axis machining, as well as the PowerSHAPE Pro CAD software for more comprehensive modeling for both components and tooling.
"The changing patterns in materials use, especially in the aerospace industry, offer both threats and opportunities to component manufacturers and the toolmakers that support them,” explained Brett Hopkins, Delcam Professional Service. "In particular, companies that have been hit by the decline in the North American toolmaking sector could find new opportunities in the composites area. Their skills in producing complex injection molds could be transferred relatively easily to the manufacture of tooling for compression molding and reaction injection molding of composites.
“Similarly, firms that have traditionally made models and patterns for the metals industry could turn to producing similar items for composites manufacture,” he continued. “Delcam has both the software and services to help companies to make this transition.”
A key step in manufacturing composites is developing the shapes for cutting the initial sheet of material. To help with this, Delcam’s PowerSHAPE has “wizards” that provide the user with step-by-step guides through the process of ‘flattening’ a complex 3D shape. Then, the unwrapped pieces can be modified to allow for edge overlaps, joint, etc., before being nested together to create the optimum cutting pattern.
For modeling, as with other CAD systems, PowerSHAPE Pro provides a number of alternative methods for constructing a surface from a given set of lines, arcs, or points. With Smart Surfacing inside PowerSHAPE, the software will choose the method that will result in the best possible surface. If the user prefers a method other than the one chosen automatically, or merely prefers to see other options, he can scroll through the alternative solutions.
However, Smart Surfacing’s selection parameters are updated automatically as extra information is added to the selection. As any additional lines or points are selected, the chosen surfacing method is reviewed and the surface is regenerated if an alternative solution has become more appropriate. Any set of surfaces can be converted into a finished model with a variety of powerful and reliable filleting and blending commands. The user simply needs to specify the desired fillet radius and the software will show a series of tracks that will match fillets of that size. Some or all of the possible fillets can then be created with a single command. In PowerSHAPE Pro, even variable-radius fillets and intersecting or overlapping fillets can be created, according to Delcam.
Another important aspect of machining composites is production time. Many composite components are still only made to approximate sizes and then trimmed manually to their final size during assembly. This process is both time-consuming and inaccurate. According to Delcam, composite manufacturers must be able to produce parts to similar levels of accuracy and consistency as suppliers of metal components before the materials can hope to achieve their full market potential: It emphasizes that its range of CAD/CAM software can help composite manufacturers and fabricators to meet those goals.
“PowerMILL 2011 makes the programming of safe toolpaths easier than ever thanks to new stock-model-engagement options that protect both the cutting tool and the machine from excessive loading,” Delcam reports. Other enhancements to the program are new editing capabilities to simplify the machining of duplicate items; more versatile control of feed-rates for leads and links; and extra functionality for sketching, plus the completion of the move to the new clearer forms for the complete range of strategies.