End mills are the most commonly used milling cutters on CNC machine tools. The following is a detailed introduction to end mills:
First, definition and characteristics
End mills are the most utilized tools on CNC machine tools. They are cylindrical in shape and generally have more than three blades. The main cutting edges are distributed on the cylindrical surface of the milling cutter, and the end surface is the secondary cutting edge. The shape of the end face of the milling cutter is center hole type or open type.
There are cutting knives on the cylindrical surface and end surface of the end mill, which can cut at the same time or work separately.
The main cutting edge of the end mill is on the cylindrical surface, and the cutting edge on the end surface is the secondary cutting edge.
End mills are divided into left spiral and right spiral, and the milling edge is also divided into left edge and right edge. The most common is right edge right spiral. The edge on the cylindrical surface of the end mill can be a straight edge or a spiral edge. However, the straight edge is intermittent cutting, with large vibration and poor surface quality; while the spiral edge is continuous cutting, with each tooth gradually cutting in and out along the cutting edge, with very little vibration, thus improving the stability of the cutting process and the surface quality of the workpiece. End mills with spiral edges are the most common.
Second, use and function
End mills are mainly used in processing fields such as plane milling, groove milling, step milling and profile milling.
End mills can also be processed by spiral processing or cycloidal processing, and can be used for various processing forms such as side processing, groove processing, and curved surface processing.
End mills are suitable for vertical cutting on workpieces and usually have longer shanks for operation on vertical milling machines.
Third, types and selection
There are many types of end mills, including flat head milling cutters, ball head milling cutters, round nose milling cutters, forming milling cutters, chamfering cutters, T-type cutters, tooth-shaped cutters, etc. Each milling cutter has its specific application scenarios and advantages.
When choosing an end mill, factors such as the hardness of the processing material, processing accuracy requirements, processing efficiency and cost need to be considered.
Fourth, precautions for use
When the end mill is working, it cannot feed along the axial direction of the milling cutter, otherwise it will affect the processing effect and tool life.
When using the end mill for cutting, it is necessary to pay attention to the control of cutting speed, feed speed and cutting amount to avoid tool vibration and breakage.
When resonance occurs in the processing system, it may be caused by factors such as excessive cutting speed, low feed speed, insufficient rigidity of the tool system, insufficient clamping force of the workpiece, and workpiece shape or workpiece clamping method. At this time, measures such as adjusting the cutting amount, increasing the rigidity of the tool system, and increasing the feed speed should be taken.
In summary, the end mill is an indispensable tool on CNC machine tools, with a wide range of application scenarios and important processing functions. When using it, it is necessary to select the appropriate end mill type and parameters according to the specific processing requirements and conditions, and strictly abide by the precautions for use to ensure the processing effect and tool life.
