Niagara Cutter N68661 Carbide Corner Radius End Mill, Inch, AlCrN Finish, Roughing and Finishing Cut, 5 Flutes, 3" Overall Length, 0.500" Cutting Diameter, 0.500" Shank Diameter, 0.125" Corner Radius

The Niagara Cutter STR540 Stabilizer AlCrN-coated carbide corner radius end mill with five flutes features the patented Stabilizer flute design, which combines variable helix angles and unevenly spaced flutes of differing lengths to allow deeper cuts at higher speeds on hard materials such as steels, stainless steels, and high-temperature alloys. The helix angle varies from tooth to tooth to reduce tool vibration and provide efficient chip removal. The unequal length and spacing of the flutes creates an out-of-phase cutting action that further reduces tool vibration and extends tool life. Five flutes produce a better finish than fewer flutes and allow for higher feed rates compared to the four-flute Stabilizer, depending on the type of material being milled and the cutting depth. Aluminum chromium nitride (AlCrN) coating provides good hardness and better resistance to chemical breakdown in high-heat applications than TiAlN, TiCN, and TiN coatings. The carbide substrate is harder than high-speed or cobalt steel, making it more wear resistant at high speeds and hot temperatures, providing longer tool life. The Stabilizer flute geometry, carbide substrate, and AlCrN coating make the STR540 suitable for machining the hard steels, stainless steels, and high-temperature alloys used in industrial manufacturing and the commercial aircraft, aerospace, and defense industries.

Corner radius end mills have a square end with rounded corners on the cutting edges to reduce chipping and extend the life of the tool. The center-cutting design has cutting teeth at the end of the tool, so it can be fed into the workpiece like a drill bit. The tool has an eccentric primary relief feature that provides better support behind the cutting edge than a flat relief, reducing tooth breakage in deep cuts. Cutting diameter tolerance is +0.000" to -0.002". The tool comes with a round shank.

End mills are designed to remove material and create multi-dimensional shapes and profiles. They have cutting edges along the outside diameter and flutes that remove chips from the cutting area and allow cooling fluids to enter. If heat is not reduced effectively, the tool’s cutting edges will dull and additional material buildup can occur. The number of flutes can range from two to eight. Two-flute designs offer the most efficient chip removal, but more flutes provide a smoother finish. The shank is the end of the tool held in place by a tool holder or machine. Center-cutting end mills can create three-dimensional shapes and profiles, and make plunge cuts similar to a drill bit. Non-center-cutting end mills are for applications such as peripheral milling and finishing, but cannot make plunge cuts.

Niagara Cutter has been designing and manufacturing precision cutting tools since 1954. Specializing in end mills, cutting mills, and saws, the company is based in New York and manufactures its tools at facilities in Pennsylvania and Massachusetts. This allows the company control over production, from substrate to coating, which is essential for customers in a variety of industries, especially aerospace and automotive.