By Derek Korn , Senior Editor
From: Modern Machine Shop
Posted on: 1/17/2013
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BobCAD-CAM is a software developer that has offered affordable, intuitive CAM packages for two- and three-axis machining applications for nearly 30 years. The company recently worked with ModuleWorks, an Aachen, Germany CAD/CAM component supplier, to support customers looking to perform more complicated work such as simultaneous five-axis machining. The result is BobCAD/CAM’s new Version 25 Four- and Five-Axis Mill software packages that enable it to offer a single programming platform for an increasing base of customers that are integrating higher-end equipment.
One way users can benefit from these packages is by performing four- and five-axis simultaneous roughing operations. Traditional approaches (even when a four- or five-axis machine is used) complete much of the roughing using three-axis movements. This not only leaves behind stair steps that must be cleaned up with subsequent operations, but extends programming time. Conversely, simultaneous four- and/or five-axis roughing tool paths can be much more efficient than a series of three-axis roughing with part indexing routines followed by clean-up of the additional stock left behind.
However, a new multi-axis tool path available in BobCAD-CAM’s four-and five-axis packages makes such simultaneous, multi-axis roughing routines even more efficient. Adaptive Roughing applies the consistent-tool-engagement-angle strategy that previously has been only available for two- and three-axis operations to four- and five-axis simultaneous movements. The company says it is the first to provide a consistent-tool-engagement-angle toolpath strategy for two through five-axis operations.
Adaptive Roughing uses arcing, trochoidal movements to maintain a consistent load on the tool. This differs from conventional tool paths that base the feed rate on cutting conditions whereby the tool is under maximum load (such as when a tool is driven into the corner of a pocket, a situation when the angle of engagement with the material is much higher than with a straight-line cut.) Maintaining a consistent tool engagement angle means the programmer doesn’t have to base the feed rate of an entire tool path on that type of worst-case scenario. The result is a faster feed rate, more consistent tool wear and the full use of the tool’s length.
Applying this concept in four- and five-axis movements is useful for pockets with a floor that bends or wraps around a cylindrical surface (see the screen shot on the previous page). It essentially morphs a consistent-tool-engagement-angle tool path between the floor and ceiling of a pocket. In addition to pockets, this strategy might be promising for select moldmaking applications.
Adaptive Roughing is just one of many toolpath strategies offered in the company’s four- and five-axis software. Others include a true swarf machining tool path as well as a variety of surface-based tool paths. The software offers 100-percent-associative tool paths and supports multi-core CPUs to reduce the calculation time of complex tool paths. Plus, the company supplies postprocessors with every seat of software.