Milling with an end mill, which is the plural of the cutting edge of cutting-off sequence, and some non-cutting edge from the state, with the rotation of the spindle, the workpiece contact to start cutting. The higher the hardness of the workpiece, the greater the instant impact piece tip contact, the higher the likelihood of damage to the tip. For this reason thickening tool tip, a cutting edge surface is made negative, reducing the groove portion of the blade root thicker, such a tool called a high hardness cutting tool.
However, non-high hardness with milling tool wear, for the actual processing in the vicinity of the critical diameter exhibit the phenomenon of friction, high hardness, wear with a cutter, the central portion of the front end in the actual machining diameter size range is very flat , can significantly reduce the processing time. Therefore, this factor must be included for consideration.
In summary, the use of appropriate line speed, depth of cut is reduced, as quickly as possible and with the feeding speed of the basic principle of the processing is not limited to small diameter tools.