FEATURE ON TOOLING

High-finish shoulder milling

According to Sumitomo Electric Hardmetal, key to the capability of the Sumi Dual Mill TSX series of higher efficiency, 90° shoulder mills is the combination of fine-carbide insert press/sintering technology with precision profile-grinding techniques. This enables the periphery ground inserts used with the new tangential cutter body design, which is available in standard, medium and fine-pitch versions, to generate high levels of surface finish.

The TSX series is based on the use of tangentially mounted carbide inserts offering a choice of chip-breakers: L for low-rigidity machine set-ups, G for general purpose operations and H where a stronger insert edge is required to support tasks such as rough, heavy interrupted and hard-steel milling, for example.
Sumitomo’s TSX shoulder mills comprise shell-type bodies between 40 and 160 mm diameter, and shank-type bodies between 16 and 160 mm diameter, to support operations such as face and shoulder milling, slot milling, and side and face-milling tasks. Two sizes of insert, each with four corners, are precision ground to accommodate 8 or 12 mm depths of cut.
A recent customer trial witnessed the milling of a workpiece made from 42CrMo4 alloy steel. Using a TSX shell cutter body combined with ACP200 grade inserts and G-type chipbreaker, the process (with coolant) was run at 270 m/min cutting speed, 0.05 mm/rev feed and 8 mm depth of cut. Not only did the Sumitomo set-up improve component wall quality, it increased the number of parts produced from 135 to 220.
For further information www.sumitomotool.com

General milling grade for steels

Dormer Pramet has launched a new milling grade for general machining applications in a variety of common engineering materials, particularly steels. Suitable for both finishing and roughing, even in unfavourable cutting conditions, the M8330 grade is said to provide a reliable and versatile option when machining either with or without coolant, in steels and cast iron. The new grade is also suitable for stainless steel, super alloys and hardened steels.

The M8330 replaces the existing 8230 grade and features a nano-layered PVD coating which is designed to offer increased resistance to thermal cracks, improved toughness and greater impact strength.
Added to more than 90 different types of existing Pramet milling inserts, M8330 is also available in a completely new range of inserts for copy milling. RCMT10 inserts offer high metal removal rates, with up to 5 mm depth of cut and strong durability. Designed to allow a high feed per tooth, RCMT10 is available in three geometries to support operations in a range of materials: geometry F is for stainless steels, super alloys and low-carbon steels; geometry M for steels and stainless steels; and geometry R for cast iron and hardened materials.
To support this addition, Dormer Pramet has expanded its current line of SRC copy-milling cutters. The SRC10 is a series of small diameter cutters available in sizes from 25 to 66 mm, and in a variety of types, including end mills, modular and shell mills. A double-negative design is deployed to provide a stable cutting action, even during roughing, making it suitable for operations such as face milling, helical interpolation, ramping, progressive plunging and high-feed cutting.
For further information www.dormerpramet.com

Bespoke tooling on short lead times

According to Walter GB, aerospace manufacturers that require special solid-carbide tooling for titanium workpieces will have to wait no longer than three weeks using the company’s newly introduced Xpress service.

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An example of the cutter options available to aerospace component manufacturers is the Prototyp Ti38 Z6-10 solid-carbide milling cutter. Featuring a newly developed substrate and PVD coating, this cutter is able to operate at cutting speeds of up to 140 m/min. In addition, multi-tooth solutions with up to 10 teeth allow the feed to be increased by up to 50%, says Walter, in turn providing an increase in metal removal rates of up to 50% compared with conventional solutions.
In one case, tool life on a titanium aerospace window frame with a tensile strength of 1250 N/mm² has been raised by 154% when semi-finishing and finishing using a Prototyp Ti40 cutter. On the same component, using a Prototyp HDC Ti38L for finishing the outer contour, tool life was extended by 116%, while cutting speed increased by 25% and machining volume by 23%.
Also, the use of Walter’s CVD coating technology for its WSM45X indexable insert which, for instance, is used in the Walter Blaxx M3255 porcupine milling cutter, is seen as pivotal. Using this tooling combination, titanium structural components are typically machined using full slotting and climb milling at a cutting speed of 45 m/min and a feed of 0.12 mm. A further option is to increase the cutting speed to 65 m/min, achieving a predictable tool life of around 60 minutes.
Customers of the Xpress tool service can use the my.Walter software to design the tool online. This will be followed by an email quote for the purpose-made tool along with a 2D drawing and 3D model; all within an hour.
For further information www.walter-tools.com

Router geometry optimised for CFRP

CoroMill Plura routers unveiled by Sandvik Coromant are designed to offer optimised milling and slotting operations in composite materials such as CFRP and GFRP. According to the company, customers will benefit from the patented geometries featured on the new routers.

When milling and slotting composite materials, the CoroMill Plura routers are used primarily in full radial engagement and at full depth of cut. In some cases, finishing passes can also be deployed. Helix angles have been carefully designed for sharpness and cutting edge strength, helping to ensure longer tool life and high-quality surface, edge and slot finishes. The range comprises three cutters: the CoroMill Plura compression router, CoroMill Plura low-helix router, and CoroMill Plura serrated router.
The CoroMill Plura compression router, with its dual 40° helix, works best with special woven glass layers on both sides of CFRP components. As there is an overlap between compressed flutes, the router performs well in thin, flat materials by reducing material vibration.
Specifically designed for smooth and burr-free finishing passes in CFRP workpieces, the CoroMill Plura low-helix (5°) router features a high number of teeth and a coating that is designed to facilitate quick cutting and protection from heat. Right- and left-helix options allow flexibility in material with challenging support conditions, such as weak or compromised fixtures.
Finally, the CoroMill Plura serrated router, with its large flute form, is designed for very high material removal rates. The geometry also offers a dual cutting action to reduce delamination and vibration, ultimately providing a single-pass solution to minimise stress on composite parts.
All three CoroMill Plura routers can be used with or without coolant.
For further information www.sandvik.coromant.com

End mill offers increased MRR

The new Eliminator series of end mills from Quickgrind is purpose-designed to increase metal removal rate (MRR) when performing five-axis machining operations. According to Quickgrind, the end mills incorporate a conical or tapered form that will deliver reductions in cycle time of up to 95%. This bold claim is substantiated by the ability of Eliminator to reduce tool-path distances while utilising the entire flute length to increase the step-down rate and subsequent MRR. Furthermore, the geometry of Eliminator reduces the potential for thermal deformation, dissipating heat from the cutting edges to extend tool life and improve surface finish.

From an application perspective, Eliminator tools are suited to semi-finish and finish-machining processes on a range of components, including aerospace turbine blades. The solid-carbide end mills are available uncoated or with Quickgrind’s Type D geometry, which features an MX coating for the machining of low- and medium-alloy steel, tool steel, cast iron and hardened steels. Alternatively, Type S end mills are XRed coated for the machining of high-temperature alloys such as Inconel, Hastelloy and titanium, as well as stainless steels.
Eliminator cutters can be used as a direct replacement for ball-nose and standard end mills. The tools are available as three- or four-flute cutters, which are offered in shank diameters of 6, 8, 10, 12 and 16 mm, which taper down to a ball nose diameter of 1, 2, 3 or 4 mm.
For further information www.quickgrind.com