Designated as shallow-pitch roughing tools for high material removal rates in the aerospace industry, the Widia 4U50 and 4U80 series are available with four or six cutting edges and harmonically designed flute geometry. In addition, users can choose from a short cut length (4U50 series) for rigidity, or a regular cut length (4U80 series).

The 4U50 has a flute length of 6 to 25 mm depending upon the diameter selected, and a necked shank that permits 3xD cutting. Diameters of 6, 8, 10, 12, 16, 20 and 25 mm are available, with a neck length from 18 to 75 mm. The stub length design includes an overall length from 57 to 121 mm, which is said to eliminate chatter and vibration, extend tool life and improve material removal rates. In addition, the tool geometry enhances swarf evacuation and creates a smooth cutting action to reduce stress and load on both the tool and machine spindle.

Likewise, the 4U80 series of regular cut length end mills for deep pocket machining are available in diameters from 6 to 25 mm, with the same overall length as the 4U50.

Both the 4U50 and the 4U80 are offered with four flutes in diameters from 6 to 12 mm, with the larger 16, 20 and 25 mm tools incorporating a six-flute geometry featuring a 45° helix for rapidly extracting chips from the cutting area. Unlike the stub length 4U50 series, the 4U80 provides a 3xD flute length from 13 to 45 mm that increases the opportunity for high-performance slotting, pocketing and ramping.

The centre-cutting end mills are coated with Widia's proprietary AlTiN-MT coating technology that works in synergy with the geometry design to improve machining performance and tool life when cutting challenging alloys.