Keys to a successful high speed machining

There are many components to an effective high speed machining process for programmers and machinists in Asia. Despite investing millions of dollars in high-speed machining (HSM) technology, often forgotten is HSM's impact on tool path programming techniques. Increasing the spindle speed, reducing the depth of cut and rounding sharp corners in tool paths are not enough for successful high speed machining.
Most conventional CAM software will cut deep features in small steps to ensure the tool is not overloaded and to minimise the impact of over-engagement. And generally, most Asian programmers and machinists find themselves either breaking tools or scaling back machining parameters, such as step-over, feed-rate and depth of cut and the value of that new high speed mill is reduced.
The challenge to a CAM system is to make passes with very small stepovers at very high feed rates. And this must be accomplished without forcing the tool to make sharp turns, because the look-ahead features of HSM controls will automatically reduce the feed rate when they detect a corner approaching.
CAM technology is evolving today to meet the specific needs for new tool path strategies to suit the HSM environment. The goal is to find the best CAM features that can help realise effective HSM.

Efficient machining in hard tool steels

Siemens PLM Software's NX offers extensive capabilities for efficient machining in hard tool steels including Z-level roughing, semi finishing, steep and non-steep area milling, uncut material removal, finishing and profiling. It uses a range of methods to ensure a constant rate of material removal - a key capability, as sudden changes are an important cause of tool breakage. One of the most important areas in CAM programming, NX maintains metal removal rates while managing tool loads. NX tracks remaining material at each cut and adjusts subsequent tool paths for best finish with least machining time and with a high degree of automation in the software.

The latest trochoidal tool-paths in NX, CAM are automatically selected to avoid over-embedding the tool. The tool path avoids the possibility of “slotting” as the tool becomes fully embedded. In NX,  the trochoidal loop radii are adjusted automatically to match stock and part geometry.
The automatic addition of intermediate tool paths in Z-Level in shallow regions leaves a constant depth of stock in semi finishing, ensuring uniform cutting in finishing operations. For optimum engagement and smoothness of finish, constant Z-Level cutting is highly effective and enables effective control of tool loading. Various options for non-cutting moves enable tangential connections between adjacent cuts. Smooth helical cutting can be achieved even on irregular shapes.
NX includes a customisable machining database allowing the user to manage and apply proven data to associative tool path operations. A data set is included for P20, typical steel for molds and dies. NX CAM enables super-fast tool path computation for Z-Level rest-milling. This allows tolerances to be tightened for highly accurate and robust rest-milling. NX tool paths are fine-tuned for high-speed machine controllers. Uniformly distributed point-point, tangential circular records and NURBS output options enable users to match the method to the parameters of each task. A key contributor to tool breakage is unwanted vibration created as the tool; holder and spindle resonate with cutter impact frequencies. The resulting rapid fluctuations in tool loading will lead to premature failure.
Siemens PLM Software offers machinists a method to calibrate their equipment and giving them the confidence to move to higher regionsAir Jordan 1