Tooling expert Walter GB says companies of every size can cash in on the benefits of high-dynamic milling – higher process reliability and faster, more cost-effective cutting by using higher speeds and feeds, as well as reduced ‘free travel’ of the milling cutter and longer tool life.
Indeed, compared to high-performance cutting (HPC), the advantages of high-dynamic cutting (HDC) can be realised when milling components of every size and in all materials, says the company.
The main differences between conventional HPC and HDC are in the movement of the cutter and the forces generated. During HPC milling, the tool takes relatively small depths of cut; during HDC milling, the machine and its CAD/CAM functionality adapts the paths so that the tool delineates during machining to the shape of the workpiece and takes greater depths of cut.
Tool engagement angle is usually very large during HPC milling, so the process forces are accordingly high which not only creates significant tool wear but also places undue stress on the machine spindle. The tool engagement angle for HDC is normally small, so the forces which impact the tool and machine are much lower.
Higher cutting parameters, less free travel and increased process stability result in a much higher metal removal rate for HDC milling.
The cornerstones of HDC are the tool, machine, CAD/CAM system and the workpiece – and the strategy is successful only when all four are in synchronisation.
Cutting values – the maximum permissible radial width of cut and engagement angle – are determined by the material, while workpiece geometry has a direct bearing on the length of cut and tool diameter. The CAD/CAM software calculates all important parameters such as milling direction, optimum path guidance, adherence to the defined maximum engagement angle and average chip thickness, then adapts them to the application.
The milling machine is ‘dynamic’ when it has excellent acceleration characteristics around tight corners, short calculation and switching times, and a wide range of speeds.
Tool selection is based on the machining operation and in accordance with the parameters predetermined by the material.
Walter works closely with CAD/CAM system suppliers and its customers to find ideal solutions to individual milling tasks by applying its Engineering Kompetenz strategies to, for example, select the correct tooling – Walter’s MD133 Supreme solid carbide cutters, for example – and by using the Walter GPS software to determine the most cost-effective machining solution based on tool and cutting data recommendations.