Lathes have many uses, some of which are less conventional than others, like gear skiving. A case in point can be seen at one of Europe’s largest specialist manufacturers and suppliers of gear racks, pinions, leadscrews and nuts, Halifax Rack & Screw (HRS), which has recently started producing round gears at its Brighouse factory in West Yorkshire.

For machining round gears accurately and quickly, the firm has invested in a gear skiving machine: an Okuma Multus U3000-2SW from NCMT. Already installed and operational, this bar-fed, multi-tasking lathe is about to be fitted with automation equipment to further speed the handling of components, free up more operator time and make the process even more efficient.
Sales engineer at HRS, Simon Matthews, who has been heavily involved in the project, says: “For the medium-to-large batch production of gears, skiving has become the technology of choice. For example, in the case of the first three gears we are producing for our US customer, Vermeer, the 25 minute cycle times for the two larger gears would be three to four times longer by hobbing or using other gear cutting machines. We opted for the Multus from Okuma, as it was the first multi-function machine manufacturer to develop a generic platform for skiving precision gears to DIN5 quality.”
A crucial element in gear skiving on a multi-tasking lathe is being able to synchronise accurately the B-axis rotary movement of the upper tool spindle carrying the skiving tool, with the C-axis rotation of the main spindle – functionality for which the Multus is noted.
For further information www.ncmt.co.uk

Even in its standard version, the C200 lathe built in Germany by Index-Werke is a productive bar auto with three turrets and two spindles that are horizontally opposed. Now, the manufacturer has introduced a tandem version with two main spindles mounted side by side and two counter spindles for even more cost-effective production. Sole sales and service agent in the UK, Ireland and the Middle East is Kingsbury.

The new Index C200 tandem, which has an identical machine housing to that of the original lathe, doubles production output in the same footprint without increasing labour or energy costs. Each of the three VDI-30 tool turrets, which can be used simultaneously, have remained the same in terms of their arrangement, power, speed and feed rate.
New, however, is the turret design, which enables five double tool holders to be mounted. Each side is equipped with identical tools in pairs, fixed or live, which are used in parallel at the main and counter spindles for simultaneous front-end and rear-end machining.
Bar stock up to 52 mm diameter is fed by the specially developed Index MBL52 tandem magazine, allowing two bars to be advanced into the lathe at the same time. An integrated handling device was also developed, whereby two grippers ensure that the pair of machined components are removed from the counter spindles and placed on a conveyor belt to exit the machine quickly and without damage.
Index’s patented SingleSlide guide system remains in use for the tandem version of the C200. Kinematically driven steel plates replace compound slides for supporting the three turrets, significantly reducing the distance between the turret centreline and the point at which it is driven.
For further information www.kingsburyuk.com

TDT Machine Tools has struck a new partnership deal with CMZ, a Spanish manufacturer of lathes and turning centres. With immediate effect, TDT Machine Tools is able to offer CMZ machines across the central belt of the UK. This area extends coast-to-coast from Lincolnshire in the East, to Wales in the West, taking in the East and West Midlands, including Hereford and Worcester, and extending as far north as Sheffield and Doncaster.

CMZ has been manufacturing lathes for more than 70 years. This family business, founded in the town of Zaldibar, near Bilbao, has grown exponentially in recent years to acquire global acknowledgement in the machine tool sector. CMZ manufactures almost 500 lathes per annum, all of which are designed to offer a life cycle of over 20 years. Over the past three years, growth at CMZ of 7%, 16% and 23%, highlights the increasing popularity of the company’s machines.
“CMZ machines are built to last for decades, without any compromise in precision or reliability,” says Phil Terry, sales director at TDT Machine Tools. “Importantly, we can supply standard CMZ lathes from factory stock in one week, which compares favourably to the five weeks typically required for machines from the Far East. Even CMZ lathes built to customer specifications are available on short lead times.”
TDT Machine Tools is able to offer the full CMZ range, which extends from small two-axis lathes, through to 18-axis triple-turret high-productivity turning centres featuring sub-spindles. Swing diameters of up to 950 mm and 3250 mm between centres, can be provided.
It is also worth noting that CMZ is well placed in that the company has its own service division based in the UK. With headquarters in Rugby, just up the road from TDT, CMZ lathes are installed and maintained by CMZ-employed, UK-based engineers.
For further information www.tdt-machinetools.co.uk

Northampton-based Scot Bennett Engineering, which supplies milled and turned parts to the automotive, agricultural, lighting and industrial sectors, has purchased its second Nakamura AS200LMYS from the Engineering Technology Group (ETG) to help it cope with a 16% increase in demand.

The single turret, 15-station live tool and twin-spindle machine will reduce cycle times by up to 25%, as well as remove secondary operations on more than 40 different product lines.
As an investment, the machine gives the company extra capacity with its milling work, capacity that will soon be used on a number of projects – including aftermarket motorcycle absorbers for an export customer.
“The Nakamura is a high-quality machine and delivers the precision, speed and flexibility that we need,” explains Rob Bennett, who took over the business from his father in 2010. “We already have an AS200 on the shop floor and know, first-hand, what it can give. This second machine will provide us with extra milling capacity and we’ve made sure that the machine has been configured exactly the same, with the same work holding and software. By doing this, we’ve removed the need for any extra training, while accelerating the installation process.”
Jon Mannion, regional sales manager at ETG, adds: “Nakamura is a very popular choice for subcontact machinists and it’s not difficult to see why. The ability to mill and turn on the same machine, with live tooling delivering a 6,000 rpm spindle, is a real game changer for firms who want speed and the ability to manufacture complex components.”
For further information www.engtechgroup.com

Citizen Machinery has added two sliding-head, twin-spindle turn-mill centres of 32 mm bar capacity to its Cincom programme. Designated L32-X LFV and L32-XII LFV, both feature the firm’s patented low-frequency vibration (LFV) software in the control’s operating system that acts in two axes to convert what would normally be long, stringy swarf into short, more manageable chips. LFV is particularly helpful when machining stainless steels, plastics and copper, and can be applied not only to turning, but to grooving, thread cutting and drilling.

Different to the two other L32 bar autos in the range, the eight-axis L32-X adds a Y2 axis to the Z2 axis on the back tool post. So does the nine-axis L32-XII, which additionally has +90/-45° B-axis swivel on the front gang tool post, where rotary tools can work at either spindle to produce angled holes. Both machines are available in 35 and 38 mm bar diameter versions, and may be used with or without the guide bush.
Citizen’s L32 design is modular, enabling users to streamline their manufacturing costs by selecting functions that achieve the optimum machine configuration, while retaining the option of being able to add extra functionality later. A workpiece conveyor is standard. Control is via the Industry 4.0-ready Mitsubishi 800 CNC, which allows up to three tools to be in-cut at the same time.
As many as 44 tools for front, back and cross machining are available in the L32-X model, while the B-axis L32-XII version accepts four fewer. The speed range of the 3.7/7.5 kW main spindle and 2.2/3.7 kW counter spindle is up to 8000 rpm. Both have a C axis for use in conjunction with driven tool stations in the three tool carriers.
For further information www.citizenmachinery.co.uk