Milling Cutter should pay attention to its near the center of the cutting speed is very small, close to "zero" , so cutting conditions are worse. Therefore, it is possible that the milling cutter axis and the normal direction of the workpiece by a tilt angle. According to the test, when the angle is about 15 ° , the tool life will reach the maximum value.
The overhang of cutting tools has some influence on the tool life in high speed machining. According to the limited test results, when the overhang of 6mm end mill is increased from 30mm to 60mm, the tool life is expected to increase to 140% to 230% .
In profiling, the milling method along the cross-section Contour (also called CONTOUR milling) is superior to the milling method along the Longitudinal Section Contour (also called climbing milling) . Because the cutting conditions of contour milling are relatively consistent, the cutting is stable, the surface roughness of the workpiece is also relatively good, and the cutting conditions of hill milling are extremely unstable, and the cutting edge is prone to collapse when the cutter is near the center, the surface roughness of the workpiece is also not ideal. In the case of hill-climbing milling, the experiment shows that the tool life of forward milling is better than that of backward milling, and that of up milling is better than that of down milling.
When milling the inner cavity, the radial force will increase sharply when the cutting tool is fed to the corner, and the peak value will reach about 170% of the normal cutting value. Therefore, we suggest the implementation of the so-called "cycloidal cutting" in the corner, so as to avoid a sudden increase in cutting force, so as to achieve a smooth cutting, extended tool life.
We should pay special attention to cooling. Oil Mist Cooling (also known as quasi-dry cutting) is relatively ideal, jet cooling, high-pressure internal cooling can also be accepted, but should avoid low-pressure, external cooling.