People call processing hardness exceeds 56hrc, or strength exceeds rm> 2000n / mm2 of the steel material is hard machining. In most cases, molding or die after the pre-processing, to go through carburizing or hardening. After pre-processing, it must set aside a certain finishing allowance. Especially when machining a workpiece with a spherical or torus-shaped, hard milling more important. Hard milling can be cut to 70hrc material hardness, surface roughness is generally required only by means of a hand-polished to achieve, which is a very expensive process step. In order to shorten the time required for manual polishing, we must take advantage of the blade having a defined geometry in milling. As hsc machining, the surface roughness of the polished surface closer: maximum surface quality rz1 of. General hard metal cutters on the market in this range are not suitable for cutting. Solve the problem of milling hard materials, a number of prerequisites must be met. For example, use the special cemented carbide substrate material, with unique geometry and the corresponding coating cutter. This means that the tool must have these three important elements. In the manufacturing process of the tool, we must pay special attention to the balance between these elements.