Published 11/8/2010

Program Safe Tool Paths

Edited by: MMS Editorial Team

The 2011 version of Delcam’s PowerMill CAM system for five-axis and high-speed machining is said to ease programming of safe tool paths with new stock-model engagement options that protect both the cutting tool and the machine from excessive loading. The software update also includes editing capabilities that provide simpler machining of duplicate items; more versatile control of feed rates for leads and links; and extra functionality for sketching.

According to the company, tool loading optimization options help overcome a constant conflict for programmers. On one hand, they want to maximize productivity by setting feed rates as fast as their machines will allow; on the other hand, they need to ensure safe speeds that will not break the tool. The need for safe machining has become more critical as a growing number of companies introduce lights-out operation, the company says.

A number of CAM programs incorporate strategies based on the extent of cutter engagement. These ensure more consistent tool load and enable higher feed rates, the company says. However, these options are usually limited to the initial roughing operations, or to only roughing and rest-roughing. The CAM software’s stock engagement technology can also be employed with the system’s finishing and rest-finishing strategies, to ensure the safest possible tool paths at all machining stages, the company says.

The key to this more comprehensive solution is the accuracy of the stock models produced within the CAM software after each machining stage has been completed. According to the company, these models give precise representations of the material still remaining on the part. This enables users to ensure that the cutter is never asked to remove more material than it can safely cut. At the same time, the stock models also ensure that tool paths are not produced where there is no material remaining, so the machine tool is never left cutting air.

New toolpath editing options are said to make it easier to produce multiple copies of any duplicated item. The user can specify an array of multiple copies in one operation, using approaches such as a number of rows and columns or a radial spacing around a central point. Once the copies have been produced, the complete series of tool paths can be re-sequenced to minimize tool changes.

Enhancements to feed-rate optimization improve control of leads and links at the points of cutter engagement and exit. A number of editing options that have been added to the sketching function enable offsetting or transforming curves, flattening 3D curves into 2D curves, or projecting 2D curves onto 3D surfaces.