Rigibore says that an engine manufacturer has gained total control over its boring processes thanks to the introduction of the company’s automated boring tool compensation system, Zenith.

The system was selected for its ability to make compensations automatically from measurement data to an accuracy of 1 µm on diameter. Maintaining much closer machining tolerances on crankshaft bearing journals not only enhances the quality of the finished component, but has a direct impact on engine efficiency and emissions.
The concept was to produce line boring bars with five semi-finish cartridges set 0.1 mm below nominal, thus allowing five ActiveEdge finish cartridges to machine all journals in a single pass. ActiveEdge line bars were automatically compensated to nominal from data provided by offline gauging that was transferred to the machine control as part of the Zenith closed-loop system.
Before installing ActiveEdge tools, the customer carried out verification checks to confirm that each cartridge could be adjusted independently in increments of 0.001 mm on diameter. With this ability confirmed, an extended live cutting trial was instigated. The trial took place on a twin-spindle machining centre, with each spindle machining 946 crankshaft bores over a 24-hour period, so 1892 in total. In this time, not a single bore was out of tolerance thanks to ActiveEdge’s intervention. The finished bores had a mean diameter of 52.965 mm with a tolerance of ±0.015 mm. During the test period, bore sizes were maintained within a variance of just 2 µm.
Prior to installing the tooling, the process of ensuring nominal size before the production run took 45 minutes on average. In contrast, Zenith allows automatic, individual cutting edge compensations to be made with the tool located anywhere in the machine, completing the setting process after an insert change within a matter of minutes.
For further information www.rigibore.com

Expanding the series of solid-carbide end mills and slot drills defined by Sumitomo Electric Hardmetal as its “global standard”, the GSX Mill series is now available. The latest milling cutters have been developed based on a fine carbide substrate to increase toughness.

GSX Mill tools also have a high transverse rupture strength and provide high levels of shock resistance with enhanced orders of consistency and reliability, especially in wet cutting conditions.
The GSX Mill series, covering tools between 1 and 25 mm diameter, has a special flute design and large rake angle. The cutters come in many varieties, covering two, three and four-flute types, in four different lengths of flute. A novel combination of flute design and rake angle enables effective chip evacuation from the cutting zone, while the specific design of two cutting edges improves sharpness and extends the type of workpiece that can be machined.
Typical end mill and slot drill applications cover surface milling, drilling and grooving, with two types of cutting edge profiles. The sharper edged S-Type is suitable for removing inside corners when finish-cutting, while the strengthened edge C-Type, having a gashed land, creates higher resistance to fracture for both roughing and finishing cycles.
The GSX-SLT slot-type cutter is a multi-purpose tool developed for plunge drilling and slot milling, having a large rake angle for efficient chip removal. Also within the GSX Mill series is the GSXVL, which is an anti-vibration, square-type cutter for shoulder milling with an optimised irregular pitch and lead angle that improves resistance to chatter.
Finally, the Sumitomo GSXB Mill ball-type cutter has two flutes and a large 30° helix angle that reduces any resistance to cutting forces, so is suitable for milling hardened steel up to 60 HRc, titanium alloys and cast iron.
For further information www.sumitomotool.com

The DoTripleMill from Tungaloy can use an octagon insert that offers 16 cutting edges which can take a depth of cut up to 3.4 mm However, if the depth of cut requirement is greater, then the same cutter body can accommodate an eight-edged square insert with depth-of-cut capability of 6 mm.

Tungaloy’s DoTripleMill is also capable of using an eight-edged round insert. There are many advantages to a round insert. Round inserts are the strongest of all cutting tool geometries and can handle several applications. Another feature of round inserts is that with a light depth of cut, chip thinning can be utilised to offer feed rates that rival high-feed cutters.
A big part of the performance advantage of DoTripleMill is found in the way the insert is secured into the pocket. The insert has a ground-in groove that circumnavigates the periphery of the insert, midway through the insert thickness. This groove acts to lock the insert into a mating protuberance in the pocket.
With conventional face-milling cutters, the neck of the screw is the only factor holding the insert down. Where the DoTripleMill uses the milling cutter pocket to wedge the insert into place, this method acts as a dovetail locking mechanism that fully secures the insert, prevents movement, accurately tracks the insert and reduces strain on the screw, which is a common issue with conventional milling cutters. This design configuration facilitates higher feed rates, improved repeatability, increased dependability and better surface finishes.
Inserts are available in both CVD and PVD coated grades. The CVD grades run at elevated spindle speed, while the PVD grades are used for sharper cutting edges. Diameters start at 50 mm and go to 160 mm.
For further information www.tungaloy.com

Two drills optimised for drilling aluminium automotive parts have been developed by Sandvik Coromant.

Suitable for machining components in medium-to-large volumes, CoroDrill 400 and CoroDrill 430 deliver high throughput and low costs, as well extended tool life and enhanced process security, says the company. The drills are supported by CoroTap 100, 200, 300 and 400, which are also optimised for tapping operations in ISO N materials and help provide a complete hole-making offer from a single source for those tasked with producing aluminium automotive components.
While both CoroDrill 400 and CoroDrill 430 are available in the Sandvik Coromant N1BU solid-carbide grade, the former can also be specified in the newly developed N1DU veined PCD grade. N1DU provides PCD across the entire cutting edge, thus offering much longer tool life. Due to PCD’s low coefficient of friction and high conductivity of heat, the tool’s cutting edges are less susceptible to built-up edge. As a general guide, Sandvik Coromant recommends the use of the solid-carbide grade when the hole count is low and handling risk is high, while the PCD grade is preferable where hole count is high and higher productivity is required.
CoroDrill 400 is recommended for drilling into solid material, as it features more flute volume for better chip evacuation. When drilling into cored material or pre-cast holes, CoroDrill 430 will perform better as it features three flutes for increased stability and holding true positon, regardless of misaligned cored holes.
Optimised features of CoroDrill 400 and CoroDrill 430 include polished flutes and precision coolant holes, with support provided for MQL. The drills are available as standard in 5, 6.8, 7, 8.5, 10.2 and 12.5 mm diameters, which correspond to M6, M8, M10, M12 and M14 thread sizes.
For further information www.sandvik.coromant.com

NCB100 from Sumitomo Electric Hardmetal is a newly developed cutting tool material specifically for hard-to-machine, high-specification workpiece materials. The use of NCB100 enables tool life to be increased by a factor up to 50 times when compared with more traditional carbide cutting inserts, says the company.

Sumitomo has introduced its first cutting insert produced from NCB100, an ultra-hard binder-less polycrystalline cubic boron nitride (BL-PCBN) cutting material, using a newly devised method of direct conversion sintering. Binders and the volumes used in producing cutting inserts can have a significant influence on mechanical and thermal properties, and hence performance, an area that Sumitomo’s binder-less development is said to overcome.
NCB100 has high levels of hardness, strength and thermal conductivity that will surpass conventionally sintered PCBN compacts containing binder materials, says Sumitomo. As a result, NCB100 creates high orders of wear resistance and stability from the cutting edge of the insert. This capability is critical when machining difficult, non-ferrous materials such as titanium alloys, cemented carbides, hard ceramics, and Ni-based heat-resisting and cobalt-chrome (Cr-Co) alloys used in medical applications.
Sumitomo reports that NCB100 has been proven in finish-turning trials against established carbide grades, where significant levels of tool life improvements have been achieved despite inserts being run at cutting speeds up to 200 m/min. The material has also been found to be highly stable when finish-turning Co-Cr alloys used, for instance, in medical hip joints. In addition, the insert material can be applied to
high-speed milling applications such as the finishing of titanium alloys and nickel-based heat-resisting alloys, at speeds up
to 700 m/min.
For further information www.sumitomotool.com