Fast and reliable milling of stainless steel, titanium, heat-resistant alloys or even CrC alloys is a huge challenge for many machine operators and tool manufacturers. To overcome the challenge, the Swiss cutting tool manufacturer Mikron Tool launched CrazyMill Cool, a product family that promises a valuable solution in a diameter range from 0.3 mm (0.012") to 8 mm (0.315"). CrazyMill Cool Ball is the newest product of this line. Its application field is the roughing and finishing when copy milling, contour milling or facemilling. The carbide endmill offers cutting depths of 2 x d, 3 x d or 5 x d has been developed specially for industries where stainless steel, superalloys and CrCo alloys are the daily business.

The medical industry, with its highly precise instruments and implants, depends on reliable, high-quality cutting tools. The same requirements exist in segments where the working material has to be heat resistant (e.g. energy industry with turbine blades, automotive or aerospace with compressors).

A straight collaboration with competent partners like carbide producers or coating specialists and the integration of different factors, such as tool geometry, grinding technology or coolant supply, results in high cutting speeds and surface quality when roughing and finishing. CrazyMill Cool features integrated coolant channels with the outlet located on the shank taper. They feed the cutting edges continuously with a consistent coolant jet and flush the chips from the cutting zone.

The form of the channels permits a maximum quantity of coolant even at lower pressure without reducing the stability of the tool. However, the smallest diameters (from 0.3 mm or 0.012") with a 3 mm (0.12") shank diameter need a coolant pressure of 15 bar to guarantee a good cooling effect.

Besides an efficient cooling, there are other parameters responsible for the tools' high performance. The grinding secondary angle guarantees a vibration free machining and (combined with a high cutting speed) a high surface quality. By changing the infeed a_p and a_e, this tool can be used for roughing or finishing. When roughing, it is possible to go with a vertical infeed a_p up to 1 x d and a horizontal infeed a_e up to 0.3 x d, when finishing infeed has to be reduced to a_p max. 0.5 x d and to a_e 0.05 to 0.15 x d, depending on the required surface quality. Roughing means working in a vertical position, for finishing it's recommended to work in an inclined angle of 10° to 15°.