Three sliding head CNC automatics, recently added to a machine inventory of some 100 single- and multi-spindle lathes, have already brought in more new work for the factory owner.

Wilco Manufacturing, Birmingham, specialises in the sub-contract manufacture of precision turned parts. Its policy is to offer customers as diverse a service as possible in three main areas: complexity of component produced, from a simple dowel to a complicated turn-milled part; batch sizes it is prepared to undertake, which currently range from 500- to 500,000-off; and delivery service, either kan-ban, schedule or discrete orders. With further diversification in mind, the company has supplemented its 100 or so single- and multi-spindle cam automatics, sprints and fixed-head CNC lathes with three sliding-headstock, multi-axis turning centres from Star Micronics GB.

In addition to broadening the scope of its manufacture, the other main driving force behind the acquisitions was to eliminate costly secondary operations performed on conventional drilling, milling and capstan machines in order to reduce manufacturing costs, improve product quality and become even more competitive.

So, when evaluating the available sliding-headstock lathes on the market, particular attention was paid to the power and speed of the driven tool stations and of the sub-spindle for reverse end-working.

It was this that led to the selection of Wilcos original Star SR-20RII lathe in October 2003, followed in autumn 2004 by the purchase of two further, identical machines.

Compared with the other short-listed sliding-headstock lathe, the Star offered 25 per cent more power on the five driven cross-working tools, which are rated at 1.2kW, as well as a 60 per cent higher top speed of 8,000 rev/min.

The machine also offered a 1.5kW(cont)/2.2kW(15min) sub-spindle motor, double the power available on the competitors machine.

Consequently the Star lathe is easily capable of drilling and tapping holes up to 8mm diameter/M8 in the back of components.

Another advantage was that the sub-spindle and four powered reverse end-working tools, one more than on the competitors model, could work totally independently of main spindle operations served by the platen.

In all, eight of the 28 cutters in the working area of a standard SR-20RII can be used in combination with the sub-spindle, allowing considerable machining versatility.

Furthermore, in respect of the front end-working tools used with the main spindle, four were provided on the Star machine, one more than on the competitors model, and again these operations may be carried out independently of sub-spindle operations.

All this may seem a little obscure, but as Martin Lane, Managing Director of Wilco points out, such enhancements in machine design translate into shorter cycle times and in some cases the ability to finish-machine a component in one hit instead of having to perform a second operation, resulting in lower manufacturing costs.

Often, Wilco has to centre, drill and tap a hole in the back of a component as well as turn the end face or O/D.

So if only three stations are provided for end-working, one of the operations would have to be carried out using a rear-facing tool mounted on the back of the front end-working attachment or in the cross-working post.

As these are both linked to the turning platen, no simultaneous machining in the main spindle would be possible and productivity could be lost.

An example of where a considerable productivity improvement has been made on the Star machines is in the manufacture of a 5/8in A/F hexagonal steel connector for the automotive industry.

Wilco used to produce it in four successive operations on a single-spindle automatic, a magazine-loaded auto and a drilling machine, followed by manual deburring.

The sum of the previous cycle times was 95 seconds and manual handling was required between the separate operations.

The same component is now machined completely in one automatic cycle, in half the time, on one of the Star lathes and with improved repeatability, 24 hours a day.

Moreover, the absence of inter-operation handling has eliminated potential damage that was previously caused on occasion to the 3/8in UNF male thread at one end, eliminating scrap or rework.

Another example that shows a big improvement is an hydraulic component produced from 0.400in diameter ground mild steel bar.

This part also used to be manufactured in four set-ups: turning, drilling and tapping a 2-56 UNC thread at one end on a single-spindle automatic; reversing the component, forming an end taper and drilling a 4.5 mm diameter blind bore from the other end; milling a 1.5mm deep by 1.5 mm wide slot along the length of the component; and cross-drilling a tiny 0.8 mm diameter hole to meet the initial hole made for the 2-56 UNC tap.

The 93-second total cycle time has been cut by over a third to 58 seconds on a Star lathe and manual handling has once again been eliminated.

Batches of typically 2,000-off are produced and the lead-time has been cut from four weeks to one, dramatically improving customer service and reducing work-in-progress.

Wilco Manufacturing obtained a DTI grant through a Regional Selective Assistance Scheme to help purchase the three Star lathes.

It enabled Lane to telescope a five-year plan to acquire the sliding-headstock lathes into one and a half years.

The original idea was to transfer work requiring multiple operations from the conventional machines to the first Star lathe.

In practice, however, when customers heard that sliding-headstock capacity was available, new business rolled in so quickly that it filled the machines capacity.

Lane confirms that between the first Star machine coming in and the installation of the other two, in excess of GBP 100,000 of new work was won as a direct result of having sliding-headstock turn-milling capability.

Furthermore, the second and third machines are currently sampling new orders from back inquiries and if these also come to fruition, a further GBP 150,000 of business will have been won partially as a consequence of having bought the first Star.

All three machines are fitted with a full length FMB automatic bar magazine and are mainly employed for producing stainless steel, steel and alloy components in cycle times ranging from 18 to 90 seconds to a general tolerance of +/-0.015 mm, which is easily held.

All work going through the machines tends to be high accuracy, complex components that would traditionally require multiple secondary operations, so the powerful cross machining and reverse end-working capabilities of the Stars are nearly always employed to extract maximum benefit from the machines.

Whereas the cam automatics are only operated during the manned day shift, all the bar-fed CNC machines run overnight without operator attendance, contributing significantly to Wilcos productivity.

The company was established in 1940 as a subcontractor serving the automotive industry, principally the Rover Group.

By the mid-1990s, over 90 per cent of the company's turnover was in the automotive sector.

With the BMW takeover, the trend at that time was for component and sub-assembly production to be outsourced to other countries such as Brazil, and for overseas-built engines to be imported rather than made here, all of which reduced the amount of work available to UK subcontractors.

Lane resolved to diversify into a number of other areas including electronics, leisure and hydraulics, the latter now accounting for 15 per cent of the companys GBP 1.4 million turnover, while the proportion of automotive work has dropped to 60 per cent.

The recent entry into sliding-headstock turning will assist the company to spread its work more widely over different industries, further reducing its exposure to the automotive sector.

It will also place Wilco in a better position to compete with the increasing number of low-wage manufacturing nations on the world scene, notably China, India and Eastern European countries.

Photographs herewith, captioned: 1.

The three Star SR-20RII sliding-headstock lathes on the shop floor at Wilco Manufacturing, Birmingham.

2.The machining area an SR-20RII, showing simultaneous front and reverse end-working in progress on a steel hydraulic component, which is now produced complete in 58 seconds.

3.The steel hydraulic component seen from both ends, showing the operations in both faces, the longitudinal groove and the 0.8mm diameter cross-drilled hole, which would be inefficient to machine without 8,000 rev/min live tool stations.

As a duty of care to its customers, sliding-headstock lathe company now fits automatic fire suppression systems as standard equipment on all new machines delivered to customers in the UK and Eire.

As a duty of care to its customers, sliding-headstock lathe company, Star Micronics GB, now fits automatic fire suppression systems from Nobel Fire Systems as standard equipment on all new machines delivered to customers in the UK and Eire. The safety equipment can also be retrofitted to lathes already in use. In response to fierce overseas competition, manufacturers and subcontractors are increasingly running machine tools 24/7 and for a large part of that time unattended.

There is always a risk of fire due to the ignition of cutting fluids and certain combustible metals such as titanium and magnesium alloys.

Nobels range of systems has demonstrated 100 per cent success in automatic dousing of fires in machine tools.

The result is minimum downtime before return to full production, as well as possibly saving the machine tool and indeed the whole factory from going up in flames.

Actuation of the fire suppression system is accompanied by automatic machine shutdown, as it is linked into the machines CNC.

Each system will automatically detect a fire and actuate suppression, but should an operator be present, the system can be triggered manually, giving complete control and flexibility.

The fire suppression systems conform to strict standards and depending on the suppression medium chosen, are manufactured to, and meet the requirements of BS5839: EN54; BS5306; NFPA11a; NFPA 750; UL2127.

All are manufactured under ISO 9001/2 and are CE marked.

As a result of the systems conforming to internationally recognised standards, some insurance companies may offer enhanced terms when providing cover for adequately protected machines.

Star GB received nine orders for sliding-headstock turn-milling machines at its open house exhibition, held from 18th to 22nd October 2004 at the company¹ s Melbourne showroom.

Star GB received nine orders for sliding-headstock turn-milling machines at its open house exhibition, held from 18th to 22nd October 2004 at the company' s Melbourne showroom. Three additional lathes were sold during October, bringing total order intake for the month to over £1.2 million. All were single-machine orders from subcontractors, three of which are new customers to Star and first-time users of sliding-headstock lathes.

Unsurprisingly, therefore, four of the orders were for Star's entry-level, 16 mm bar capacity machine, the SB-16.

At the other end of the scale, among the three 32 mm capacity machines sold was the new SR-32J platen-configured model, on show for the first time in Europe, as well as a top-end capability ECAS-32T turret-type machine.

It is the high flexibility generated through the four-axis, 16 tool all-driven turret of a CNC sliding head auto that enables a combination of complex 3D forms to be milled.

It is the high flexibility generated through the four-axis, 16 tool all-driven turret of the latest Maier ML ProLine 32E CNC sliding head auto that enables a combination of complex three-dimensional forms to be milled and, through a fully programmable 0.01deg angle positioning axis, precise in-cycle machining from the turret of angled internal and external features and holes. Now available through StarragHeckert UK of Brackley, the 12-axis Fanuc 160iT CNC, all servo-controlled machine is targeted at more complex part machining requirements such as those found in medical implants, telecomms, hydraulic and fuel injection type applications and often required in difficult to machine high tensile materials. Mounted upon a polymer composite base with the highest levels of thermal stability, rigidity and therefore minimal effects of vibration, three totally independent carriages enable up to three tools to be engaged on a workpiece at the same time.

The construction also supports high feed rates up to 32m/min reached with an acceleration to full speed within 1mm of travel and enables idle times to be minimised thus maintaining full use of the highly flexible tooling arrangement without any loss of productivity.

The sliding head mill/turn centre combines two-axis main and three-axis secondary spindles with an octagonal turret having 16 all-driven positions with tools mounted side by side and positioned via an X-axis cross feed.

Altogether, there are 36 tool positions of which 26 can be driven by 1.5kW motors to provide a wide option of tooling arrangements to satisfy high productive 'one-hit' cycles.

The main and opposed spindles both have C-axis positioning with 5.5kW, 6,000 rev/min drive and a stroke of 220mm for the main Z1 and 230mm of travel for the opposed Z2 spindle.

Surrounding the main spindle is an X-Y tool carrier able to hold four powered cross-machining tools and six turning tools.

The three-axis back working attachment, which has its own Y-axis feed, is able to position three static and six live tools arranged in a grid fashion that maximises setting flexibility and creates short tool movements to engage with the workpiece.

A fully programmable 120 bar high pressure coolant system is optional to the standard system along with quick-change tool holding system.

Specialised cycles such as thread whirling, polygon turning and forming, right angle and adjustable angle drilling/milling units are also available along with part support and separation for machining long components.

Citizen's new K-Series CNC sliding head automatic lathe combines two opposed spindles offering up to six turning tools, eight end-working tools and seven driven tools.

Citizen's new generation K-Series CNC sliding head automaticlathe combines two opposed spindles offering up to six turningtools, eight end-working tools and seven driven tools to givehigh precision single-hit cycles for parts up to 12 mm or 16 mmas an option. The stylised machine presents new Citizen livery oftwo shades of silver with a polished stainless highline andlift-up guarding for easy access to the working area. Fastfloor-to-floor cycle times and flexibility of setting were keydesign briefings on the new K-Series represented by the initiallaunch of the K12-VII.

The main spindle has a 3.7 kW drive, some50 per cent more powerful than the previous entry level B-Seriesmachines of Citizen and produces 15,000 revs/min.

The maximumspeed of the sub-spindle is 10,000 revs/min.

The main spindle hasC-axis as standard and the sub-spindle 150 indexing with anoption of full C-axis.

A massive 200 mm of headstock stroke isachieved through a synchronised motor driven guide bush.Unusually for this type of machine, the tool shank is 12 mm toenable heavier, faster cutting cycles from the higher rigiditymachine.

There is also an option for 10 mm shank tooling.

Thesesquare shank tools are mounted on the highly efficient yoke-styletool carrier set around, and close to the spindle, whichminimises tool travel.

And, even with the short distance betweentool and workpiece, the rapid travel rate is 32m/min, some 50%higher than the previous B-Series machine range.

Central tosimplicity of programming but also for ultra-fast dataprocessing, the Citizen K12 uses a special version of the latestFanuc 31i Series control system with newly developed processors.Citizen's own software minimises idle time, makes most ofthe high acceleration available for axis movements andcapitalises on the capability for optimising the cutting process.The machine is compact requiring a floor area of just 930 mm by1680 mm.

Norfolk-based Mussett Engineering is using two DECO 20a automatic sliding head CNC lathes from Tornos to manufacture parts round-the-clock for a leading producer of writing implements.

Norfolk-based Mussett Engineering is using two DECO 20a automatic sliding head CNC lathes from Tornos to manufacture parts round-the-clock for a leading producer of writing implements. Mussett Engineering, located 10 miles southeast of Norwich, claims to be the largest sub-contract engineering facility in the East of England: boasting a workforce of over 100 and an array of some 50 CNC machine tools at its 33,000 sq ft facility, the ISO9001:2000 accredited company is probably right. Although in recent years the company has tended to specialise in the manufacture of complex parts in batches of 10-100 for the aerospace, automotive, oil, petrochemical and compressor sectors, some contracts still call for batches of up to 20,000 components.

For this reason Mussett Engineering can keep its two 10-axis DECO 20a sliding head autos busy 24 hours a day.

'We originally acquired the machines to tackle a very small diameter part for the telecommunications industry,' says managing director and founder, Gordon Mussett.

'However, they are so versatile that we have since used the machines to produce parts for a number of different sectors, including medical and armaments.

At present they are both running non-stop producing internal and external components for writing implements.' Mr Mussett says that the Tornos machines have helped cut cycle times dramatically in comparison to the company's conventional twin turret, twin head machines.

'I recall one part, a regulator for a pressure gauge valve, which previously took 6 minutes 35 seconds on a twin turret, twin head lathe that was subsequently reduced to 1 minute 45 seconds on a DECO 20a,' he confirms.

'There are many more examples where cycle times have been at least halved, with many operations reduced to just one.' Yet despite the significant reductions in cycle time and number of operations, Mussett Engineering witnesses no compromise in quality from its Tornos machines.

'The quality of the machines and the quality of the products they produce were primary reasons behind our decision to buy Tornos,' explains Mr Mussett.

'If we get our bar preparation right, these machines have no problem holding micron tolerances time-after-time.' A three-shift system allows Mussett Engineering to run 24 hours a day for nearly seven days.

Using only one operator to oversee both Tornos machines permits the company to price its products extremely competitively in what has become a tough marketplace.

Yet such is the economy of the machines that Mr Mussett says he doesn't always need large volumes to bolster the bottom line.

'We've put batches as small as 200 on the Tornos machines,' he says.

'For long, slender shaft work there isn't much that can beat these machines, even for low volumes.' Such is the success of the current contract for writing implement components that both Tornos machines are fully loaded for the foreseeable future.

'It's true that we haven't got much capacity to sell on these machines at present,' says Mr Mussett.

'The only way we can fit other jobs in is to get ahead and make a gap in the schedule, but that's not a bad situation to be in is it?' he says light heartedly.

The pattern of growth at Mussett Engineering shows no signs of abating.

In fact, it is only the local shortage of skilled labour that is holding the company back.

Such is the extent of the problem that Mr Mussett has resorted to advertising as far afield as the Midlands in an attempt to attract skilled people to relocate.

'If we could find 25 skilled people tomorrow, we could find jobs for them,' he says.

'We will expand only as fast as we can find the right personnel.

However, we do not let our customers down.

We offer realistic delivery times and stick to them.

For this reason we have probably turned down as much work as we have taken on lately.

It is easy to say 'yes' when new work presents itself but I don't believe in making promises that will be tough to keep.' With a bulging order book Mussett Engineering has to get maximum output from all of its machine tools and the DECO models are no exception.

'Thankfully the reliability of the Tornos machines has been exceptional,' concludes Mr Mussett, 'which is a relief because we cannot afford to have a single moment of downtime at present.

Without doubt, the best solution in terms of productivity and feasibility is to proceed with the complete machining of the parts in a single chucking operation using one machining unit.

Every year in Europe, roughly 700,000 people suffer a hip fracture, which is frequently linked to osteoporosis. The medical facilities currently available mean that rapid surgical intervention can be conducted to reduce the fracture by applying plates and retaining screws, thereby allowing patients to quickly regain their mobility. The hip screws used for surgery are highly complex parts that require numerous machining operations involving swarf evacuation.

The highly resistant materials used in these implants including stainless steels and titanium often entail several rough-working, finishing and deburring operations.

Without doubt, the best solution in terms of productivity and feasibility is to proceed with the complete machining of the parts in a single chucking operation using one machining unit.

Thanks to the A-line products from Tornos (the Tornos Deco 20a in this case) it is now possible to machine specific parts in minutes.

The Tornos Deco sliding head lathe is fully adapted to this family of parts.

It drastically simplifies allocation of the various machining operations from the bar (main spindle) and for back operations (counter-spindle).

The kinematics of the Tornos Deco (12 numerically controlled axes all with simultaneous interpolation) allow up to 4 tools to be used simultaneously and execution of back-operations is 100% in hidden time.

The lathe and various devices developed to date offer numerous facilities for different types of machining operations, giving finished parts in a single set up.

The procedure to manufacture hip screws involves turning, centering/drilling/reaming, high pressure drilling to 120 bar, tapping, hexagon broaching/swaging, external hexagon milling, external thread whirling in back-operation mode, deburring, part support and over 20 tools to conduct the numerous operations.

The Tornos Deco 20a sliding head lathe lends itself particularly well to hip screws, due to its dimensional geometry, chucking facility, re-chucking for back-operation and facility to change between main operations and back operations.

Process Improvements Tornos continually improves its machines for the medical sector and the main technical reason for further improvement to the overall machining process of these difficult materials is to provide the operator with improved versatility and flexibility during setting up work or when retooling.

This can be achieved from pre-adjustable tool systems - available both for the fixed tools and rotating tools.

The setting up or retooling times are significantly reduced, which further reinforces the well-known productivity of the Tornos Deco lathes.

Benefits have also been obtained from the introduction of 'coolant through' tool holders to bring about improved swarf management.

Another addition is the simultaneous machining facility with respect to roughing and finishing (Balanced turning), which leads to good swarf management, increased tool life and improved surface quality.

The main sequences for machining a hip screw on the Deco a lathe involve hexagon swaging, external hexagon milling with two tools simultaneously and end piece support, back operation thread whirling in hidden time and back-operation high pressure drilling at 120 bar using a guide bush.

A UK sliding headstock turning specialist has replaced its last operating cam automatic lathe with a CNC sliding headstock machine - bought straight from the catalogue.

Sliding headstock turning specialist, Auto Screw Products, doubled its shop floor area in April 2005 by expanding into an adjacent unit on the East Gillibrands Industrial Estate in Skelmersdale, UK. It was the latest initiative by the new owner, Mike Worsley, who bought the 35 year old company in April 2003. Since buying the company, he has been replacing the company's single-spindle cam automatics with CNC sliding headstock lathes from Star Micronics GB, of which there are currently eight on site working unmanned 24h a day, seven days a week.

The last cam auto was replaced by the latest Star, an SR-32J, which was bought 'sight-unseen' from the catalogue, such is the subcontractor's confidence in this supplier.

The first Star machine the company purchased was an SH-12 - an early model that was relatively simple to operate.

To extract maximum benefit from the seven subsequent CNC lathes, which have a sub-spindle and a large number of tools, many driven, for in-cycle front-, cross- and back-working, the company was heavily dependent on help and advice from the supplier, especially at the outset.

Assistance with applications engineering and programming has been readily available from the Star team in Melbourne, Derbyshire, according to Worsley, who also confirms that after-sales service is prompt and the few problems that have arisen have been solved quickly.

He says that the supplier's positive approach and overall willingness to 'hand-hold' have been key to Auto Screw's continuing purchase of Star machines.

Worsley cited an instance of a drawing that he faxed over to Star, whose engineers responded within 30 minutes with the advice that an extended nose collet would allow the awkward part to be turned.

The relevant collet was supplied straight away from stock to allow production to start the following day.

Components are machined in mild and stainless steels, titanium, brass and aluminium, batch size normally being in the range 200,000 down to 100-off.

Most parts need back endworking and/or driven tool operations and none requires manual handling onto another machine for one or more subsequent operations.

A big advantage with modern CNC sliders such as the Stars when dealing with smaller runs is the ability to reset the lathes in less than an hour if it is a repeat job, or a little longer for a new component.

A cam auto takes up to a day to reset, resulting in much lower machine availability and consequently higher unit production costs, which are in any case elevated by the frequent need for second operations.

Auto Screw regularly achieves 150h production time per week from its Star lathes out of a total of 168h, equating to 89% availability.

Worsley suggests that cam auto shops in the UK are in decline, as long runs are needed to make them economical, but these have mostly gone overseas.

However, if UK subcontractors invest in CNC lathes, fixed- or sliding-head, their greater reliability coupled with better component consistency and accuracy resulting from one-hit machining can win even long runs back.

He mentioned a contract for 350,000-off gearbox parts that was recently awarded to Auto Screw by a German car manufacturer owing to poor component quality and long lead times from a Malaysian subcontractor.

The arguments for replacing cam autos with CNC sliders are compelling, says Worsley.

In his own subcontract business, elimination of second operations and introduction of long periods of unattended running on the Stars have allowed the headcount to be cut from 17 to seven in two years.

At the same time, turnover has risen 50% due to increased output and higher added-value production.

These factors have improved profitability.

People that talk of the demise of UK manufacturing may take heart from Auto Screw's experience.

The CNC sliding head lathe's ability to machine components in a single set up has eliminated the need for second operations, driven tooling performs milling, slotting and drilling operations.

Hullmatic Engineering Co, based in Earls Colne, Essex is a major player in the UK turned parts industry, predominantly for clients in the diesel automotive sector. To help it produce 18 million components a year, the company relies on its selection of 10 Deco CNC multi-axis sliding head lathes from Tornos. Currently celebrating its 30th anniversary, Hullmatic was a family-owned business until a management buyout team led by director Peter Pledger, took over the reins last year.

The new team is already building on Hullmatic's success as a supplier to the commercial diesel automotive sector, with customers that include Delphi, Perkins and Caterpillar.

The 72-employee company is a specialist at bar turning and has an impressive array of machine tools.

As well as Deco sliding head models Hullmatic owns over 20 single spindle automatics, over 20 multi-spindle automatics, five fixed head CNC lathes and five rotary transfer machines.

The first Tornos machine arrived following a visit to the UK's MACH 1996 machine tool show.

It is testament to the technology, reliability and performance of the Deco CNCs that the company proceeded to purchase a further nine models over the following six years.

The Tornos Deco 2000 models currently on site include four Deco 10a machines, three Deco 20a machines, one Deco 13a, one Deco 13bi and a Deco 26a.

All but one of the Deco CNCs is fed using Tornos Robobar bar loaders.

'The big advantage the Deco CNC machines provide is the ability to machine components in a single set up'.

'The machines have eliminated the need for second operations entirely'.

'We use the driven tooling extensively for milling, slotting and drilling operations,' explains Peter Pledger.

Batch sizes on the Deco machines range from 500- to 10,000-off, with selected machines dedicated to producing families of parts.

This particular strategy helps keep set-up and changeover times to an absolute minimum.

Programmed off-line, only one operator is required to oversee four Deco CNC machines, which operate day and night, five days a week.

Components are machined from steel and non-ferrous materials to tolerances of around 0.015mm.

'The Deco machines have been fantastic for us'.

'Their consistency in terms of roundness, concentricity and surface finish is second to none'.

'A reject is a really rare occurrence'.

'Also, we find the machines are very responsive'.

'Over the years we have had experience of programming a lot of turning machines, but when it comes to producing a first-off from a new program, the Tornos Decos have been the best I have seen at meeting demanding drawing tolerances and characteristics,' continues Pledger.

Hullmatic purchased its Deco machines to complement the company's existing turning technologies'.

''Whatever turning machines we buy have to be competitive,' adds Pledger'.

''If the sums did not work out for the Decos then we would not have proceeded, but in terms of saving second operation work, the benefits have been enormous.' Hullmatic also says the multi-tool turning is a major advantage in maintaining competitiveness.

It allows the company to perform roughing and finishing operations 'downstairs', while a form tool is used 'upstairs''.

' 'We have a big mix of machines and technologies,' concludes Pledger, 'which allows us to be highly responsive in terms of lead-time, and the Tornos Deco machines play a large role in helping us meet our deadlines and keep our customers happy.'

Deploying up to 21 tools, the Citizen L20 VIII CNC sliding head automatic offers 40% saving in non-productive cutting or idle time when compared against the machine it replaces.

If small precision parts up to 32 mm diameter are price critical and accuracy and consistency of production is paramount, then the latest developments by Citizen, the world-leader in CNC sliding head lathe technology, have much to offer at EMO 2005. At the exhibition, visitors will have the chance to see the European launch of the latest Citizen L20 lathe series, the first European showing of the Citizen RO7 super high speed lathe and the latest variants of the competitively priced Citizen K12 and K16 machines. Available through NC Engineering of Watford, the up to 21 tool Citizen L20 VIII is able to demonstrate a massive 40% saving in non-productive cutting or idle time when compared against the machine it replaces.

The linear motor driven Citizen RO7 VI with subspindle and 13 tools, of which two are driven, is totally new employing the same fast cycling technology of its smaller capacity sister machine the RO4 launched a year ago.

The RO7 VI with subspindle is specially developed for 'one-hit' high precision mill/turning components up to 7mm diameter by 40mm long at up to 16,000 rev/min with the linear drive creating ultra-fast acceleration over the short axis strokes at a rapid traverse rates of 20m/min.

Meanwhile, the K12 and K16 VII new generation machines with five-axis control, able to simultaneously front and rear machine a component at both spindles using six turning tool positions, also employs four driven tools, four front and four back drilling tools.

The K-Series machines redefine the productivity gains possible to lower the cost of producing mill/turn parts using CNC sliding head technology with the added bonus of competitive pricing for the installation.

Referring to the higher efficiency of the new generation Citizen L20 VIII, managing director of NC Engineering Geoff Bryant describes a series of test piece machining comparisons carried out by Citizen against the previous machine where overall savings in lost time varied between 39% and a massive 66%.

The 3.7kW, 10,000 rev/min main spindle and 1.5kW 8,000 rev/min subspindle machine also has the benefit of increased acceleration and its rapid traverse rate improved from 20m/min to 32m/min in each axis.

The main and subspindle can be employed for simultaneous machining cycles including turning and drilling and through tool overlapping on entry and exit from cuts, idle time and also vibration is further reduced.

On the new L20 even control start up time has been reduced by 75% with instant shut-down and any screen switching time is reduced by half.

The machine setter also benefits from wider guarding access and a long part adapter option also enables components up to 600mm long to be automatically unloaded.

Specialised fastener manufacturer's CNC sliding-head automatic lathe is slashing production times and providing the capability to quote same-day order turnaround if necessary.

One of the UK's leading subcontract manufacturers of specialised fasteners and other turned parts, Vaughan Jones in Wetherby, Yorkshire, has invested in a third Star sliding-headstock lathe to extend its pursuit of one-hit machining to components of up to 32mm diameter. The Star SV-32 lathe has taken over from fixed-head turning of complex parts, slashing production times and providing the capability to quote same-day order turnaround if necessary. Vaughan Jones' joint managing director, Roger McGlone, cited the case of a typical socket screw which previously required five separate operations: blank and turn roll thread diameter; face, centre and drill; broach; clear broach chips from the bottom of the socket; and thread-cut or roll.

The accumulated cycle time total was between 4 and 8 minutes, depending on component size, and lead time from order to delivery used to be one month.

The same job is now completed in one visit to the twin-spindle, multi-axis Star SV-32 in a cycle time of 1.5 to 2 minutes and additional operations such as head drilling can also be carried out in-cycle.

Not only is immediate turnaround of urgent orders possible, but economic batch size is also reduced and so too is the amount of work-in-progress (production inventory) on the shop floor.

Vaughan Jones started its investment in sliding-headstock machines in 2001 with the installation of a Star SR-20R lathe of 20mm bar capacity, followed in 2003 by a second, identical machine.

Continued Hornby, 'We had one hundred or so cam autos and plug-board machines operating 10 hours a day and basically we were getting nowhere.

We decided on a rolling programme of replacing these outdated lathes with sliding-headstock CNC models, having satisfied ourselves that this was the way forward rather than going along the fixed-head route, which would have curtailed our one-hit machining strategy.

Very few of our components need a second operation now.

Hornby said: 'The other considerable benefit of installing the Stars was the advent of year-round 24h operation, trebling available hours compared with a manually-operated auto.

Moreover, the majority of productive hours on a Star are minimally manned, resulting in labour cost savings as well.' The latest Star SV-32 has the capability to deploy 80 tools in the working area whereas even with diversification into more complex parts such as bar-turned nuts and couplings, only six or seven tools are currently used to produce any particular component.

Likewise, the capability of the Star to produce special features such as off-centre and angled holes around the circumference or in the end face of a component are scarcely used.

Hornby's reason for installing this machine was, however, not only to expand Vaughan Jones' fastener range but also to diversify into the subcontract production of more complex parts, a service which he is actively marketing both within and outside his customer base.

Materials vary widely and are often difficult to machine, hence the addition of high-pressure coolant to the latest Star lathe.

They include high-tensile, stainless and mild steels, brass, bronze and nickel alloys as well as aircraft materials and plastics.

Manufactured to international standards and customers' specifications, Vaughan Jones' high quality products find their way into diverse industries including defence, aerospace, mining, medical, telecommunications, machine tools, tooling, motorsport and automotive engineering.

n a twin-turret, twin-opposed-spindle bar automatic, three tools can cut simultaneously and accurately thanks to a 'world-first' use of a kinematic drive to replace turret compound slide.

A 'world first' is claimed by German turning machine manufacturer, Index, for its new C-Series of twin-turret, twin-opposed-spindle bar automatics, which see the disappearance of the conventional compound slide for turret movement. In its place is a patented guideway system employing two plates sliding directly over the 75 deg slant bed. The turret is mounted on the front plate while the rear retaining plate is kinematically driven in X and Z.

The advantage of this system is that the distance between the turret centreline and the point, at which it is driven is shorter than for a compound slide, making it several times stiffer.

The result is greater rigidity and better damping, leading to higher accuracy machining, even for strenuous applications involving intermittent hard turning and reaming.

Tool life is also extended.

The turret and drive plates are fitted with ceramics-coated, hardened tool steel strips at top and bottom which slide over a third plate of surface-hardened cast iron fitted into the bed, the latter plate being effectively sandwiched between the other two.

The parallel kinematic drive to the rear plate is effected by three ballscrew-actuated rods at the back of the machine, two vertical and one horizontal.

Glass linear scales provide positional feedback.

The system is faster than a compound slide, allowing rapid traverse rates of 25m/min in X and 50m/min in Z, and acceleration of 1G.

As a result, the manufacturer says that the lathe reduces cycle times by between 10 and 30% compared with other twin-turret, twin-spindle lathes on the market.

The compact turret design contributes to a small machine footprint, allowing four C-Series lathes to fit in the space occupied by three equivalent turning machines from other manufacturers.

Additional space in the working area also makes for better access and chip evacuation.

Both turrets are equipped with a 70mm Y-axis for even greater versatility when mill/turning highly complex components.

Available in two sizes through sole UK agent, Geo Kingsbury Machine Tools, the Index lathes are called SpeedLine C42 and C65, the numbers representing the maximum bar capacity in millimetres.

The 6.5 tonne machines are being built at the rate of one per day at the Index factory in Esslingen, where an 18-stage flow line and adjacent turret assembly line have been set up at a cost of EUR 1 million.

A full C-axis and 27kW of spindle power are provided at both ends, delivering top speeds of 6,300 rev/min and 5,000 rev/min for the respective models.

Clearance between the 140/160mm diameter chucks for between-centres work is 615mm.

The patented, air-cooled spindles are manufactured in-house, allowing close quality control to be maintained.

The opposed spindle is not only powerful but also has the unusual option of 150mm of X-axis movement in addition to 600mm of longitudinal travel.

By electronically coupling the movements with the X/Z motion of a lower, double-sided, 24-tool turret (optionally available in place of the single-sided version), Index provides the ability to have three tools in cut simultaneously.

This is achieved by deploying the upper 12-station turret and the left face of the lower turret to machine a component in the left hand spindle while the 'slave' right hand spindle follows the latter turret around, enabling a parted-off component to be machined using the right face of the lower turret.

In other words, the X- and Z-axis movements of the lower turret resulting from the cutting cycle in the left hand spindle are continually allowed for in the programmed movements for back-working.

Driven tool capacity is 8kW/6,000 rev/min, available at all 12 stations of each turret.

Noteworthy also is polygon generation using a head mounted directly on the counter spindle rather than on a turret, ensuring vibration-free machining and hence greater accuracy and longer tool life, especially when cutting alloy steels.

Three sliding-headstock lathes equipped with high-pressure coolant have revolutionised SS component production at one of the UK's leading aircraft engine pipe assembly suppliers.

Three Star sliding-headstock lathes equipped with high-pressure coolant (HPC) delivered at 2,000 lb/in2 (140 bar) have revolutionised stainless steel component production at B and D Patterns in the West Midlands, UK, one of the leading European suppliers of pipe assemblies to aero engine manufacturers. The Hinckley company supplies around 100,000 pipe assemblies a year in 1,300 variants to Rolls-Royce, requiring the manufacture of 500,000 individual components in 850 variants of which 25 are different types of union nuts, threaded adapters and ferrules. They are machined from S80 stainless (EN57), a corrosion-resistant aircraft steel, high in nickel and chromium, which is challenging to turn as it produces long, stringy swarf that is difficult to chip.

B and D had been soldiering on with the problem for many years, producing half of its requirement of these components in-house in batches of 200- to 500-off using a selection of its 28 fixed-head lathes without HPC; the remainder it subcontracted out.

However, against a background of increasing orders the company decided to upgrade production, opening a satellite unit in nearby Narborough in the first half of 2005 and installing its first three sliding-headstock lathes - two SV-32s and an SR-20R from Star Micronics GB - all with HPC equipment as part of the turnkey solution.

The benefits were immediate and dramatic.

As B and D managing director Ian Burton explained, 'Whereas our operators previously had to interrupt the turning cycle on each machine every hour to prise off swarf that had wrapped itself around the component and tools, this no longer has to be done on the Stars with HPC.

Consequently, higher speeds and feeds can be used.

There is no need, for example, to waste time centring, drilling a pilot hole and then drilling a hole to full diameter using three successive tools.

An 18 mm indexable-insert drill can be fed straight down the centre of a 32mm diameter, S80 bar in one operation without fear of swarf clogging the hole.

Burton added: 'A further advantage is that, whereas the old cutting conditions invariably created large burrs on the components that needed removal by hand at a bench, the minimal burrs that are now left can be removed by rumbling batches of components, saving considerably on second-operation work.' In the case of the nuts and adapters, such deburring was in fact a third operation, as the twin-spindle fixed-head lathes formerly used had a single turret without live tooling.

So although parts could be turned at both ends in one set-up, they had to go onto a machining centre for second-op cross hole drilling and milling.

With the Star multi-axis mill-turning centres, all operations are completed in one hit.

The result is that the larger nuts and adapters can be mill-turned on any of the Stars in cycle times that are on average 25% less and there is no re-fixturing on a machining centre for prismatic operations.

Ferrules are turned in half the time as they do not need to be milled or drilled.

B and D's original intention had been to retrofit HPC to some of its existing lathes and to invest in fixed-head mill-turn centres, two initiatives that it has in fact started in order to improve production of other parts.

However, when they visited Star's open house in Melbourne, Derbyshire, UK, last year they discovered that, for the production of nuts, adapters and ferrules, the sliding-headstock configuration with HPC was capable of faster cycle times than an equivalent fixed-head, twin-spindle lathe with driven tooling.

Mr Burton says that the Star sliders resulted in like-for-like cycle time savings of 25 to 50%t compared with those offered by fixed-head mill-turn lathes they investigated.

Currently the Narborough shop is running 13h/day, but production will be ramped up to 24h/day, five days a week by the end of 2005.

The two SV 32mm bar machines are devoted to the larger sizes of union nut and threaded adapter while the SR 20mm capacity lathe produces the smaller varieties and ferrules.

The three machines were delivered by Star as total turnkey packages with all ancillary tooling and cutting tools, and program suites fully proven prior to delivery.

At Star GB's open house in June this year, B and D placed an order for two more Star machines for delivery in September to cope with increased demand.

The extra lathes combined with the implementation of 24h operation will create spare sliding-headstock mill-turning capacity that Burton is currently looking to fill.

He believes that their experience in machining exotic materials well qualifies them to carry out subcontract work for the medical industry in particular.

In conclusion, Burton commented, 'We looked at other sliding-headstock lathe suppliers but liked the robust build of the Star machines.

We took up references from a number of customers and were particularly interested in comments from 'mixed users', i e, firms using sliders from two or more different suppliers, whose comments steered us towards the Stars.'

Claimed to be the most precise CNC turning machine available on the market - machining to within +/-1 micron - will be shown by Tornos among several innovations.

Following the April 2005 launch of the Deco 8sp and Multideco 32/6c turning centres at Moutier; the Swiss manufacturer has announced that it will be extending its product range in June 2005. The new Multideco 20/6be and Deco 20s machines will enable customers to execute simple parts efficiently. At the EMO exhibition in Hanover, on 14-21 September 2005, Tornos will present yet another new Multideco - the 20/8d.

The September launch will bring the number of new products presented by Tornos to five within seven months.

The Swiss manufacturer is astoundingly demonstrating how its policy of reviving innovation implemented in 2003, is now bearing fruit.

All the new innovations admirably complement the manufacturer's existing product range without jeopardising the well established products already on the market.

Occupying a dominant place in the high added value sector, where the parts being executed require fairly complex to highly complex operations, Tornos wants to extend its presence in alternate market sectors and provide machine tools that are more finely tuned to the complexities of various parts.

Market trends are increasingly forcing component manufacturers to invest in products that are adapted to the parts being executed.

Hence with the (s-line) and Multideco 20/6be, simple part manufacturers will have their own finely adapted products.

At the other extreme, the ranges are beginning to acquire further potential to execute more complex parts with the Multideco 32/6c and 20/8d.

Products to be presented by Tornos at EMO: Single spindle: * Deco 8sp - the most precise machine available on the market - machining to within +/-1 micron.

A Specialist machine catering for mini hard disks and other precise applications.

* Deco 13a - fully equipped machine to execute a highly complex medical part - a sector for which the machine 'works wonders'.

* Deco 20a - this machine produces alternate medical parts that make the best use of its vast machining facilities.

* Deco 20s - 'World Premiere' - the second machine in the (s-line) range.

Simplicity is the key word.

Multi-spindle: * Multideco 20/6be - a well priced Multideco machine with a guide bush to execute simple parts.

Depending on circumstances, part execution is possible with savings of up to 30% compared with the conventional yet impressive Multideco machine.

* Multideco 32/6c - the facility of fully completing complex parts by way of back-working operations is expanding.

This machine also has part handling and an integral palletisation system.

* Multideco 20/8d - 'World Premiere' - the Multideco 20/8d has a motorised spindle - offered for the first time by Tornos.

This technology was always rejected by the company because it was previously impossible to obtain sufficient power.

Tornos now offers a brand new motorised spindle system with power that is matched nowhere else on the market.

The Multideco 20/8d also offers another original innovation to maximise production time - the dual counter-spindle system.

* TB-Deco - the exceptional programming software will be presented in its latest version - the TB-Deco 2006.

This new version provides modules (ADV, CAM interface) so that you need only purchase those families with the required functions.

CNC sliding head automatics that have a large recess under the main spindle allow a sub-contractor to turn difficult-to-machine PTFE components under 'lights-out' conditions.

After 50 years of turning PTFE, Clacton, UK-based Dalau has every right to call itself a specialist in machining this plastics material. Typical PTFE components made by Dalau include insulators for the electronics industry, connectors for the telecommunications sector and various aerospace and medical parts. Dalau makes over 100 million PTFE and plastic components a year, to help maintain a lead in the market, the company has been a long-term user of turning machines from Tornos.

In the mid 1980s Dalau installed its first Tornos cam-driven automatic, the company now has 45.

In recent years the shift has been towards Tornos Deco CNC sliding head models and the company now owns four Deco 20 and seven Deco 10 machines.

The most recent addition is a pre-owned Deco 10, which was installed in January 2005.

'As a general rule of thumb, straightforward components that only require a single operation are loaded to the cam-driven autos, while anything more complex, perhaps involving PCD drilling, milling or second operations of any kind, will be put on the Deco CNCs so they come off complete,' explains Philip Alston, production and QA manager for machined components at Dalau.

Although Dalau sometimes undertakes batches up to 1 million, typical batch sizes are around 500 on the Deco CNC machines, which means a fair amount of changeovers and set-ups.

'All of our setter/operators are trained off-site at Tornos and we have found this provides more than enough grounding for them to be competent at creating the programs offline and setting the machines,' adds Alston.

PTFE has become enormously popular because of its insulating properties, chemical resistance, low co-efficient of friction and high temperature resistance (up to 260 deg C).

However, the excellent design characteristics of PTFE are countered by 'difficult' machining properties.

The machine shop at Dalau is a temperature-controlled environment as PTFE components are subject to expansion at elevated temperatures making it difficult to hold tolerances in the realm of +/-0.015mm.

'Many sub-contract machinists will not touch PTFE,' says Alston, 'But with the help of the Tornos machines we have gained the experience to make us a leader in our field'.

'The reliability of the Tornos machines is first class, which is exactly what we require for rapid throughput parts.' In the past five years, Dalau has diversified into machining other plastics materials, which has become a growing market.

Around 75% of Dalau's output is exported.

Another problem with machining PTFE is the continuous 'string' of swarf it produces when cut.

To overcome this difficulty Dalau uses bespoke tooling with an exceptionally sharp edge.

The company also says that one of the benefits of the Tornos machines is the large recess under the spindle that allows swarf to fall away.

Some machines produced by alternative suppliers do not have this, which allows swarf to accumulate and create problems.

In negating this difficulty the design of the Swiss-made Deco sliding head machines allows Dalau to run lights-out operations overnight, a capability that has become critical in its battle with competitors from low wage economies.

Quality is another key issue, Dalau has developed its own SPC system as part of its TQM system that is linked to the CNC control of the Deco machines.

The innovative system allows operators at the ISO 9001:2000 accredited company to monitor every dimension and characteristic on every drawing in real time.

If a problem occurs it can be rectified immediately and not after an entire batch has been produced.