FEATURE ON CNC LATHES AND TURNING CENTRES

GM CNC launches Victor VMT turn-mill

When it comes to one-hit machining, the new VMT series of multi-tasking turn-mill centres from Victor has a lot to offer. Available in the UK from GM CNC, the VMT range features 15kW twin built-in turning spindles and a 22kW swivelling B-axis milling spindle. Available in four variants – the VMT-X200, VMT-X260, VMT-X360 and VMT-X400 – the series is suitable for everything from the unmanned machining of small complex parts to the heavy-duty machining of large components.

As standard, the VMT range features a FANUC 0i-TF CNC, hydraulic chuck with soft jaws, chip conveyor, a Renishaw automatic tool presetter, through-spindle coolant and a hybrid lubrication system. Optionsincludes a steady rest, bar-feed interface, part catcher, automatic doors, sub-spindle and more. A Meehanite cast base provides a platform for elevated cutting parameters and improved tool life.

From a specification perspective, the VMT-X200 and VMT-X260 are 8 and 10-inch chuck machines with a 660mm swing-over-bed and a maximum turning length and turning diameter of 1376and 1075mm respectively. Serving the spacious work envelope are two 15kW/4200rpm turning spindles on the VMT-X200 and a 22kW/3500rpm main spindle and 15kW sub-spindle on the 75mm bar capacity VMT-X260.

For larger components, GM CNC offers the 12-inch chuck, 3000rpm VMT-X360 and the colossal 15-inch chuck VMT-X400.Both provide 30kW spindle power and a bar capacity of 91mm (106mm optional). The largest machines in the range provide an 1120mm swing-over-bed and a maximum turning length and turning diameter of 2148and 2100mm. All machines demonstrate flexibility through the 12,000rpm 15/18.5/22kW high-winding B-axis milling spindle that can rotate through -30/+210° with an indexing resolution of just 0.001°.

For further information www.gm-cnc.com

From seven operations down to two

It is only within the past five years that Nuneaton-based subcontractor Oaston Engineering, which specialises in work for the aerospace and biotechnology industries, has embraced sliding-head turning. July 2018 saw the arrival of the firm’s first sliding-head lathe, a 20 mm bar capacity Cincom L20-VIIILFV from Citizen Machinery UK. It was followed in October 2022 by a second, larger model, a 32 mm capacity Cincom L32-VIIILFV.

Oaston Engineering’s managing director Sean McCarthy says: “We were always led to believe that sliding-head lathe operation was a dark art and that you need to produce large batch quantities, say 50,000, to justify setting them for a new run. We had been looking at the technology since MACH 2008 and, a decade later, when the Cincom L20 was delivered, we discovered the myths were untrue.”

Oaston Engineering had a particular job in mind for the Cincom L32: the production of a light aircraft pump camshaft from martensitic stainless steel.

The component, which is produced from 1.25-inch bar, formerly needed seven separate operations: outside diameter turning and grooving; milling on a machining centre; two separate turning operations in offset fixtures to machine the cams to a dimensional tolerance of 0.07 mm; drilling a longitudinal bore on a machining centre; cross drilling a tooling hole in another operation; and off-site grinding of two spigots to within 0.015 mm.

The camshaft produced in this way required a total of 18 minutes 30 seconds of cutting time, plus inter-machine handling, as well as 30 to 60 seconds for deburring and more time for inspection at each stage. Now, six of the operations are performed in one hit in less than 15 minutes on the Cincom before the part goes out for grinding.

For further information www.citizenmachinery.co.uk

Turn-milling gear parts for premium for klifts

Owing to their high rigidity and damping properties, Index Werke says its machines are suitable for the complete machining of complex workpieces, including the integration of gear teeth. The Czech Linde Pohony plant knows this all too well, recently decommissioningits existing Index G400 turn-mill machines, after 20 years of service, and investing in six new Index G420 models. The new turn-mill centres should achieve amortisation within three years. Index machines are available in the UK via Kingsbury.

Head of production and technologyPetr Vitásekand his team tested various offers and decided once again to go for Index.

“Few suppliers were able to offer a machining centre that is equipped with two turning spindles, two turrets and a powerful motorised milling spindle that masters power skiving technology,” he says.“This gives us decisive advantages, particularly since we are able to achieve complete machining with our new Index G420 machines. Before, we had to use a lathe, a milling machine and a gear cutting machine.”

The investment allowed Linde Pohony to increase the productivity of its machines and, at the same time, save space in the production hall and thus increase productivity per unit area.

A special Indexpower skiving cycle and user-prompted input screens for workpiece, tool, process and correction data ensure easy operation.

Miroslav Vařečka, head of production engineering, mentions dry machining as a further advantage: “Compared with the former machining technique, it’s no longer necessary to clean off any oil residues on the workpieces, which implies time and financial savings.”

He adds: “We can use our turn-mill centres not only for shaft production, but also for other tasks, such as manufacturing transmission housings.”

For further information www.index-werke.com

Nakamura turning centre gets even faster

At September’s EMO exhibition in Hanover, Nakamura-Tome CEO Shogo Nakamura provided the crowds with a presentation on the Nakamura-Tome WY-100V turning centre. Now available in the UK from the Engineering Technology Group (ETG), the presentation discussed how Nakamura is making its fastest machine even faster.

The new flagship machine is a twin-spindle, twin-turret turning centre with both turrets offering Y-axis capability. With the ‘V’ in the machine name denoting ‘Velocity’, Shogo Nakamura says: “The machine cuts the burden of manufacturing by giving faster cycle times that enable customers to make more workpieces in a shorter time.”

Looking at the hydraulic component that was machined at EMO in a single operation with complex milling, drilling and turning cycles, the CEO explains how the part is machined with a 30% cycle time reduction: taking the cycle time from 536 to 375 seconds. It is achieved with new ChronoCut software technology that eliminates non-productive time.

The hydraulic component machined at EMO ran through some of the key areas where the Nakamura-Tome WY-100V is slashing cycle times. One example was demonstrated on holes drilled around the periphery of the part, using both turrets drilling simultaneously to reduce the drilling cycle time by 56%. This was followed by the rigid tapping of eight holes on the face of the turned part. The ChronoCut technology tapped the holes at 4000rpm and retracted the taps at 8000rpm, conducting very high-speed synchronisation of the Z-axis travel with the milling rotation. Previously, the maximum synchronising rotation speed during rigid tapping was around 3000rpm, but with ‘V’, it is now possible to synchronise up to 8000rpm.

For further information www.engtechgroup.com

Okuma presented CNC innovations at NORTEC

Earlier this month, Okuma exhibited at NORTEC in Hamburg, presenting its high-performance Multus B300II multi-tasking machine, which features an optimised machine design and efficient specifications. Visitors to the production and manufacturing technology trade fair could also see the intelligent OSP-P500control. Okuma machines are available in the UK from NCMT.

At Okuma’s stand, visitors could witness for themselves the extensive range of solutions offered by the Multus B300II in detailed demonstrations and live machining sessions. In addition to turning and milling, the machine is also capable of high-speed inclined-axis machining.

Okuma says that the machine delivers the high-performance machining of entire small and medium batch sizes with its two-spindle design and a main spindle speed of up to 5000 rpm. The integrated multi-tool function maximises time savings, while the fully redesigned machine provides more possibilities for ergonomic working.

The Multus B300II has a 225° B-axis range. The base offering features a 40-tool ATC, with an optional 60-tool ATC available upon request. Notably,the H1-turret has a 0.001° Baxis and compound-motion Yaxis for machining flexibility. The main spindle is equipped with a full-contouring Caxis.

Okuma’sMultus B300II uses the company’s proprietary collision avoidance system for optimal machining quality and performance. This function prevents collision-related damage to machines and workpieces during process simulation, even before production begins. Potential collisions are detected early and processes stopped if necessary.


Okuma also showcased the new version of its OSPCNC at the trade show. It provides users with even greater ease of use, incorporates sophisticated precautions against cyberattacks, and ensures maximum efficiency and precision thanks to intelligent upgrades. The OSP control also helps to reduce CO2emissions due to its energy efficiency.

For further information www.okuma.eu