Says Thilo Mueller, manager of solid carbide end milling at Kennametal: “Last year’s IMTS [Chicago in September] presented the first wave of the Harvi end-mill family, which included Harvi I, Harvi II, and Harvi III geometries in diameters ranging from 16 mm up to 32 mm. The new offering builds on that, with additional sizes and several completely new cutter styles. This increases Duo-Lock’s versatility, giving even more customers an opportunity to leverage its proven strength and accuracy.”
Note: Video shows Haimer Duo-Lock explanation; Duo-Lock is licensed by Kennametal
Duo-Lock is a modular end-mill that has the performance of solid carbide tools. It uses a proprietary, double-cone locating surface similar to that of Kennametal’s KM or KM4X tooling design, offering radial runout values of not exceeding 5 micron and Z-axis coupling repeatability of 10 micron or better. And since tool to tool repeatability of 50 micron is assured, there’s no need for offset adjustment or offline presetting when changing tools. It’s also extremely rigid, with a unique and also proprietary “intelligent” coupling thread that absorbs 25% more torque than its nearest competitor. The result is that Duo-Lock can take 1xD full-width slotting cuts and side mill up to 50% radial engagement along its entire 1.5xD cutting length, even in titanium and similar high-strength alloys.
Duo-Lock modular end-mills are now available in much smaller sizes, starting at 10 mm. Corner chamfering and rounding tools have been added to the line as well, in addition to a broad assortment of new geometries. For example, several new “corn cob” style roughers are being introduced. One has a wavy profile that creates small chips for better chip evacuation during heavy metal removal. A ball-nose style rougher leverages the same geometry but is designed for 3D profiling in mould making and similar applications. And an “aerospace friendly” version has a unique geometry that reduces cutting forces when machining high temp alloys, as well as corner radii that reduce chipping.
For finishing operations, Kennametal has developed a cutter with six flutes and a 45° helix angle similar that of the Harvi III “aerospace expansion,” but modified for better performance in steel and stainless steel. Another series has nine to 19, depending on the diameter, and a proprietary W-shaped cutting edge and unequal flute spacing, eliminating chatter and improving surface finish in high-temp aerospace alloys, even at higher feed rates.
Depending on the geometry and cutter size, four to six flute Harvi versions are available, as are several PVD-coated micro grain carbide grades. These include KCSM15, designed for titanium and other high-temp aerospace grade alloys. KCPM15, suitable for steel, stainless steel, and cast iron, and the multilayer KC643M, a go-to grade for wet-cutting a wide range of materials. All grades can be used to machine metals up to 52 HRC, and all are excellent at reducing depth of cut notching, edge wear, and cratering in difficult materials.
Finally, Kennametal has developed the MaxiMet, two-flute and three-flute high-shear end-mills that rip through aluminium for highly productive roughing, while still generating square walls and smooth floor surfaces when finishing thanks to a precision-ground wiper facet near the corner.
Kennametal is also expanding its toolholding offering through the addition of several long-reach straight and conical steel shanks, which can be cut to size for specific needs. This is in addition to the extensive assortment of HSK, PSC, CAT, DIN and BT-flange toolholders already in place.
