FEATURE ON CNC LATHES AND TURNING CENTRES

Streamlining gear cutting processes with ETG

Machining gear components demands impeccable precision levels.And although dedicated gear hobbing and skiving machinesare common throughout industry, manufacturers often face issues with multiple set-ups and the application of jigs and fixtures. This challenge exacerbates when considering additional factors such as the shortage of skilled workers and the excessive floorspace required for multiple dedicated machines. According to the Engineering Technology Group (ETG), it is possible to eradicate all of these issues with Nakamura-Tome turn-mill centres. ETG is the UK representative for Nakamura-Tome machines.

A multi-tasking machine can change the situation because it performs turning, milling and gear cutting in a single process. Integrating these processes significantly reduces set-up changes, contributing to more efficient production. Moreover, machining quality remains at the same level as dedicated machines.In many cases it improves due to fewer set-ups.


Both gearhobbing and skiving have their own set of advantages. Hobbing is suitable for manufacturing high-volume parts and external gears, while skiving is for producing parts ranging from low to high volume. Skiving applies to both outer and inner gears, and when machining close to the walls on the end of a gear. It is possible to perform hobbing, skiving and other cutting methods on multi-tasking machines, producing various gear types such as spur gears and helical gears.

When investing in a Nakamura machine from ETG, the ‘Smart Support’ software solution simplifies the creation of special machining programs developed by Nakamura-Tome through a conversational programming interface.Recently, the software introduced a gear hobbing function that now enables users to create dedicated programs by inputting variables in accordance with guidelines. To enhance user-friendliness, the software incorporates graphical images that guide operators through the process. For further information www.engtechgroup.com

Citizen machine helps TAS rebalance business

Around 20 years ago, Gareth Davies started Burton-on-Trent company TAS Engineering as a steel, stainless steel and aluminium fabrication shop.In 2014, he established a machine shop to add extra value to the products the company was forming and welding. Today, there is a pair of three-axis vertical machining centres on-site and a trio CNC lathes, the latest of which is a pre-owned Cincom L20 sliding-head turning centre from Citizen Machinery.

What prompted the purchase in October 2023 of this 20-year-old lathe, the company’s first sliding-head model, was a desire for more efficient turningof components in various materials from bar up to 20 mm in diameter. A case in point is the ongoing production of a 16 mm diameter, 316 stainless steel magnet holder, which is welded to a small, laser-cut and bent plate to form part of a safety unit for industrial switchgear. The turned component, of which 200 are required per month, was previously produced complete on one of two fixed-head, twin-spindle lathesin a 2.5-minute cycle.

It was apparent that the steel magnet holder could be produced more quickly on a modern Citizen L20 twin-spindle sliding-head turning centre due to the faster axis motions of the gang tool carriers on the former compared with the turret movements of fixed-head lathes. However, Davies was surprised to find it was possible to machine the part more than three times faster on the Cincom: the cycle now takes just 48 seconds.

He says that although the purchase price of the lathe was only about 24% of the investment needed for a modern 20 mm capacity L-series Cincom, he was treated by all Citizen Machinery UK staff as though he were purchasing a new L20.

For further information www.citizenmachinery.co.uk

Bharat Forge Daun relies on Emag machines

Unusually sophisticated components and high-strength materials for high-tech applications, like stator housings for electromobility with tolerances in micron range, are among the machining challenges tackled by the specialists at Bharat Forge Daun in Germany. At the centre of this activity areseveral vertical turning lathes (VTLs) from Emag, which operate around the clock, five days a week.

The vertical design of thesemachines played an important role in the investment decision, asa horizontal machine from another manufacturer had caused difficulties in the past. Annoying chip clusters would form, requiring manual removal two or three times a shift.

“It was therefore obvious to us that we should carry out these processes in machines with a vertical design, because their unhindered chip flow prevents disruptions,” explainsChristoph Steffens, head of mechanical engineering at Bharat Forge Daun. “Our objective was to achieve maximum process reliability.”

Another factor in the decision in favour of Emag was existing knowledge: the machine tool manufacturer used examples from other customers toshow how its machines optimise stator machining – with low non-productive times and high-precision handling processes. Integrated automation, including a pick-up spindle and lateral conveyor belt, ensures fast processes, while the stable base body is made of Mineralit polymer concrete.

Last but not least, the response time and the expertise of Emag’s service department play an important role for Bharat Forge Daun. A regional service technician is always on site within a few hours and solves any problems directly.

“So far we have always been helped with minor faults in record time,” says Steffens.

For further information www.emag.com

Mazak showcases next-generation Integrex

Taking centre stage on the stand of Yamazaki Mazak at the recent Southern Manufacturing exhibition was its Integrex i-200H S multi-tasking machining centre. The machine forms part of Mazak’s i-H series, which culminates 40 years of multi-tasking innovation and learnings.

As with all models in the i-H series, the i-200H S features a flat-fronted design with rear-mounted tool magazine to accommodate the growing requirement for automation while maintaining accessibility for the operator. The i-200H S can adopt a variety of automation solutions, including bar feeders, articulated arm robots and gantry loading systems.

The 5000 rpm main spindle receives support from a compact 12,000 rpm milling spindle with a versatile B-axis range of -30 to +120° for the complete machining of complex components. An equal 65 mm diameter bar capacity across both spindles allows for balanced cutting while maximising component rigidity.

Mazak’s i-200H S offers control via the company’s SmoothAi CNC, which incorporates a suite of software packages to deliver the practical application of AI, digital twinning and automation. The model on display at Southern Manufacturing featured the new smooth oscillation cutting program, which is built into the SmoothAi CNC. Smooth oscillation cutting provides chip control for further process stability, even when machining challenging materials.

Alan Mucklow, Managing director UK, Ireland and national distributors at Yamazaki Mazak, says: “Manufacturers need their machines to work harder than ever in order to remain competitive and drive productivity. The Integrex i-200H S is ideally suited to servicing subcontract demand across a wide variety of sectors, while its compatibility with diverse range of automation systems can help manufacturers maximise machining output.”For further information www.mazakeu.co.uk

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