By embodying automatic thread chasing and Acme- threading cycles, a range of electronic lathes is billed as a natural successor to the manual centr4e lathe.
West Yorkshire-based lathe manufacturer Harrison has embodied automatic thread chasing and Acme- threading cycles to its Alpha T (Touchscreen) range of electronic lathes - enhancing the lathe's productivity and boosting company claims that the machine is the logical successor to the manual centre lathe and the natural choice for any manual lathe user wishing to upgrade its production machinery. The Alpha T's electronic thread chasing facility can pick-up and clean the threads of a component in much the same way as the operation can be carried out using the compound slide of a manual centre lathe. The Alpha T is much quicker and simpler however - requiring little more than thread type, thread pitch and diameter information to be selected on the machine's Fanuc Quickpanel touchscreen control to initiate automated thread chasing.

The integration of automated Acme thread cutting cycles - alongside existing DP, MOD, TPI and Pitch thread cutting cycles - also enhances the lathe's growing reputation as one of the best thread cutting lathes on the market.

Harrison has incorporated these increased capabilities after in-depth consultation with its customer base to develop the Alpha T concept further _ a concept aimed at designing a lathe that, at least on one-offs and small batches, has the accuracy, flexibility and speed of a CNC yet is as easy-to-use as a manual centre lathe.

The Alpha T is also extremely competitive on price - especially when 'extras' such as DRO, X/Z axis mechanical stops, high speed threading, taper turning and copying attachments are added to the cost of a standard centre lathe.

Harrison claims that it can train a manual turner to a high level of proficiency on the Alpha T within two days.

Two days which can turn-around the competitiveness of a small turning operation by rapidly increasing productivity from the same personnel and same skills base.

Starting point for training is operating the Alpha T as a modern centre lathe, making use of the machine's integral DRO for tool positioning, and electronic handwheels for saddle and cross-slide movement.

Other controls are minimal - a spindle stop/start lever and a variable speed control rotary dial.

Constant surface speed (CSS) is a standard feature on the range.

The next step is the progression to 'semi-automatic'mode - in effect, the use of electronically controlled programs that replicate the mechanically controlled operations of a manual lathe.

This requires the simple inputting of information through clearly marked icons on the touchscreen to program electronic stops (a highly accurate replacement for the mechanical stops available on a manual centre lathe); taper turning (replacement for the conventional compound slide on a manual centre lathe); and automatic thread cutting (replacement for the mechanical threading unit on a manual centre lathe).

Consolidating on the confidence gained during 'semi-automatic' operation the trainee is then taught to combine manual operation, stops and taper turning within fully automated 'box cycles'.

Again, clearly marked icons guide the operator through the sequence of operations.

A further and final lesson is dedicated to the Alpha's off-line CAD/CAM system, the AlphaLink.

The AlphaLink system is remarkably easy-to-use, replacing the hydraulic copy turning mechanism of the manual centre lathe with a powerful and intuitive drawing and simulated machining package.

The AlphaLink system gives the operator the ability to manufacture complex components normally associated with more sophisticated machines such as full CNC lathes.

Using the AlphaLink program, component drawings - with sophisticated features such as blended radii, multiple radii forms and multiple undercuts - can be generated quite simply using a standard personal computer.

Once the program is complete it can be saved and/or downloaded to the Alpha T, through the RS232 port.

Not only is the CAD/CAM package easy-to-use, but it is also safe, allowing the machining routine to be simulated 'on-screen' before being downloaded to the Alpha.

Even the exact tooling can be simulated, by making selections from the Alpha's 'virtual'tool library.

'The Alpha T can offer massive benefits to users who upgrade from traditional centre lathes,' says Harrison Sales Director David Smith.

'One such advantage is that the Alpha T can accept small-to-medium runs of complex components - work which a small, manual turning facility might well refuse because it is beyond its scope, and, even if it could carry out the work, wouldn't be profitable.

This type of work is not only possible on the Alpha but it is also profitable due to the lathe's excellent productivity.' 'I don't think the average centre lathe user appreciates how much quicker a machine of the quality of the Alpha T can be,_'he adds.

'For example, take a simple task of cutting a 2mm pitch thread on a typical 50mm bar - it will be finished on the Alpha before set-up can be completed on a manual lathe.' 'To cite another example, Harrison and distributor RK International recently demonstrated an Alpha T to customer Gerhardt, of Tottenham, London, who required three 50 x 350mm aluminium test pieces to be turned to surface finish levels of 1.55 microns Ra.

The billets are used for manufacturing printing cylinders therefore surface integrity of the finished product is crucial.

The Alpha completed the work in about half the time normally taken by a centre lathe and achieved surface finish levels of 0.45microns Ra.

Needless to say, the customer bought an Alpha T after witnessing the test.' David Smith sums up: 'I truly believe the Alpha T is the next logical step in the evolution of the centre lathe.

A number of spindle speed, main motor and between-centres capacity improvements - up to 8000mm between centres - have been made to heavy duty CNC lathes.
Ward CNC of Sheffield, the exclusive UK agent for the Hankook Protec range of two-axis horizontal CNC lathes, has revealed a number of spindle speed, main motor and between-centres capacity improvements across the range. In addition, control technology has been standardised to Fanuc 21i-T for the models 5N, 7NA/7NB and 9N. Swing diameters over the bed ranges from 530mm on the Protec 5N to 950mm on the 9N, the largest in the range, while distances between centres now range from 1000mm to 8000mm (instead of 6000mm), respectively.

Spindle speeds range from 7 revs/min (instead of three) to 1,600 revs/min on the 5N and two (instead of four) to 1,000 revs/min (rather than 1,250 revs/min) on the 9N, with main drive motors uprated to 26kW.

Typifying the high quality of build and cost-and-performance specification available from one of South Korea's leading machine tool builders, the construction of Hankook Protec lathes is based on a double-walled and ribbed one-piece meehanite cast iron bed with induction hardened and ground precision slideways for maximum stability and accuracy.

Standard features include servo motors on both axes, four-jaw independent chuck, square tool post with curvic coupling, cooling equipment, machine lighting, two-speed tailstock quill adjustment and infinitely variable feed rates.

Options include various chucks (hydraulic and three-jaw scroll-type), automatic tool post and live centre.

Five different Protec models are available from Ward CNC, including the 9N semi-CNC variant with CNC and dual electronic handwheel control to enable users to quickly move into productive mode since minimal CNC training is necessary.

Installation of a CNC lathe and a horizontal machining centre has provided significant productivity and flexibility benefits for a workholding equipment manufacturer.
Installation of a Daewoo Puma 12L CNC lathe and an ACE H400P horizontal machining centre from the same Korean manufacturer has provided significant productivity and flexibility benefits for workholding equipment manufacturer, Thame Engineering, located in Long Crendon, near Aylesbury. The ACE H400P has proved to be around 40 per cent more productive than the vertical machining centre that it replaced, and is equipped with Thame's own design of high capacity workholding system. Likewise the Puma is much quicker and easier to set up than its predecessor and provides improved finish and accuracy.

UK agent, Mills Manufacturing Technology, supplied both machines.

Thame Engineering is a leading supplier of standard and special chuck jaws as well as specialist workholding solutions for machining applications.

Its major strength is in development of 'smart' clamping solutions, some of which use vacuum or freezing techniques, for lathe-based machining of irregularly shaped components.

An innovative feature of some of these is the capability to reposition the workpiece in- cycle, thereby maximising single set-up productive capability.

In one instance a clamping solution developed by Thame, which allows the vacuum clamped plastic component to be rotated through angles up to 20 degrees in situ, has enabled a manufacturer of surgical prostheses to cut lead-time from around seven days to three-and-a-half minutes.

This astonishing reduction is a result of the fixture eliminating the need to leave the part to stabilise to size after machining.

Said David Handley, Thame's Technical Director, 'Our business is divided roughly 65:35 between supply of standard soft jaws and bespoke workholding solutions.

As well as chucks from 20mm to over 2000mm diameter, the specials side also embraces development of fixtures for prismatic machining applications.

Long Crendon is the main site but we have subsidiary companies in Bremen, Germany and Chicago, USA, with exports accounting for around 35 per cent of sales.' Machining requirements range from batches of two or three components up to around 400-off, so flexibility is highly important to Thame.

The company regularly works with machine tool suppliers on turnkey solutions for end users so the ability to fast-track production of components is essential.

Equally, production of standard jaws demands efficient machining methods so that the products remain cost competitive.

'We have around a dozen CNC machines of various types,' Handley explained.

'In addition we maintain a number of conventional machines for 'jobbing' work.

When we acquired the Puma CNC lathe it was as a direct replacement for a fairly antiquated NC lathe.

One of the key attractions of the Daewoo machine was its large swing.

We can turn over 550mm diameter on the machine, providing capability to turn jaw sets that are destined for use on vertical turning lathes.' Peter Mason, Thame Engineering's Managing Director, commented, 'We felt that the machine offered very good value for money as it is capable of tackling a wide range of work.

The integrated setting probe makes tool set-up straightforward while availability of constant surface speed ensures much more consistent finish compared with the old machine.

Although we bought the Puma for chucking we can use it for bar work utilising our own bar pulling device for batches of up to 400 components.' As with the lathe, it was capacity that persuaded Thame to invest in its Daewoo ACE H400P horizontal machining centre.

Whereas the Puma is used for a wide range of work, the machining centre has a more production-oriented role.

It was the 500kg table load of the ACE machine that particularly recommended it, which Handley said was considerably higher than the capacity of other machines he looked at.

'When we design fixtures for customers' machining centre applications we aim to maximise the number of components that can be mounted,' Handley continued.

'In this way the productivity of the machine is enhanced.

We originally used a vertical machining centre to produce the soft jaws but the horizontal machine provides much better access to the component for machining as well as improved control of swarf.

It also has through-tool coolant to maximise drilling performance.' Each of its two pallets is equipped with a four-sided tombstone fixture with clamping positions for twelve sets of jaw blanks.

Each face of the cube can accommodate different components if required.

Once loaded, the machine performs two operations on each component; serrations are machined in a separate operation to complete the component.

'Use of the ACE H400P has provided improvements in both productivity and quality,' said Mason.

'When we made these parts on a vertical machine they had to be chamfered manually but this step is now included in the CNC program.

Part of the machine's productivity advantage arises from being able to set it to operate unmanned between shifts and the fact that it does not need to have the operator in attendance other than to load/unload and set-up.' In fact the performance of the machine has been good enough for Thame Engineering to invest in a second, identical machining centre to boost capacity on standard jaws.

'We have been very satisfied with the performance of both Daewoo machines,' Handley concluded.

'In addition, the service from Mills Manufacturing has been very good and the training has been excellent.

Our purchase of a second HC400 is attributable to this, combined with operator familiarity and the fact that there appears to be no alternative that is more suitable for our purposes.'

Forged synchroniser rings for manual transmissions demand high accuracy and they are being machined in CNC lathes in faster cycle times when compared with front-loading chuckers used before.
VTL Automotive turned to Pollard Mori Seiki CNC lathes to mass-produce a variety of forged Synchroniser Rings for manual transmissions. Compared with the output from front-loading CNC chuckers, the Pollard Mori Seiki CL Series CNC chuckers machine the rings in faster cycle times, to tighter tolerances and with virtually zero reject rates. 'Our main products are synchroniser rings and selector forks for manual transmissions, said VTL Automotive Managing Director, Bruno Jouan.

'We forge and machine some eight million rings/year for a number of OEMs, including Renault, Ford, New Venture Gear and Volvo.

Deliveries are in tightly controlled, sequenced, just-in-time batches and there is no room for rejects.' Forged high tensile brass is not the easiest material to machine, 'We forge individual rings from blanks, which have been precisely sawn from extruded seamless brass tube.

After heat treatment, the hardness of the forgings is up to 230 Brinell.

It is a hard material and can rapidly form a built-up edge on the turning tools if the tool geometry is not right.' 'The rings look a deceptively simple job.

But it is not easy to turn and bore these rings within a few microns and hold tight tolerances over a typical batch size of 5000-8000.

Also batch sizes and ordering patterns can fluctuate, so VTL Automotive have to have the flexibility to be able to change over quickly from one component to another.

Under the previous ownerships of Sagar Richards and laterly Valeo Transmission the Luddendenfoot factory was producing the rings successfully on twin-spindle, front-loading CNC chuckers.

By the early 1990s, the synchroniser ring designs were steadily evolving, and the trend was towards more sophisticated designs with even tighter tolerances.

'We felt that the existing machines would not be able to cope with the tighter tolerances demanded by our customers, we were not able to reduce cycle times and improve efficiency any further, as machining on the old chuckers was restricted by the clamping system then in use,' explained Sales and Technical Director David Clegg.

The synchroniser ring has to be located from the forged blocker teeth to allow tooth facing and OD turning be performed with the ring clamped internally, and then chamfering, boring and internal threading be carried out with the ring clamped externally.

In the late 80's and early 90's we had examined a number of ways of increasing machining output and tightening up tolerances.

'At one time, we operated front-loading chuckers, Wyvernmatics and Herbert Cridans,' related David Clegg.

'The work then involved lots of different operations, a one man-one machine strategy and work-in-progress stocks.

We looked for a new machining concept - we even considered rotary transfer machines - before acquiring our first Mori Seiki CL-20 from Pollard Mori Seiki in 1991, and a second in 1992.

After some development work, we acquired five CL-20s during 1995-96 and later, six CL-203s in 2000.' The company had entered into a joint development with Pollard Mori Seiki to develop machining methods for a new generation of synchromesh rings.

Pollard had had considerable experience in applying Roehm chucking systems to the Mori Seiki CL Series of CNC lathes, explained Pollard Mori Seiki's Area sales Manager, Rod Lockwood.

David Clegg added that the important considerations were the actual orientation and location of the precision forged rings in the chuck.

The limits for clamping pressures and spindle speed had to be determined before 'lobing' occurred in the rings (clamping pressure, coupled with the tooling pressure during boring could cause the rings to lobe outwards from between the three clamps).

On the twin-spindle chuckers the rings had to be 'tooth faced' first to create a location face.

The clamping mechanism was a three jaw pull back system, pulling back onto the location face which allowed boring, threading and chamfering.

This system was replaced by the earlier CL-20s.

Applying a tailored R”hm pullback chuck on the CL-203s with tailstock support meant that the rings were machined in one operation with a shortened the cycle time.

The first Mori Seiki CL-20 CNC production lathe, complete with a twin-gripper gantry loader was delivered in 1992.

The gantry loader would pick a forged ring blank from a palleted stack, transport the forged ring to an orientation device, from there to load to the chuck (removing the finished part first) and return a machined ring on a finished stack The orientation devices use vibration to rotate the ring until a certain radial position is registered and detected by a light sensor, the gantry loader would then re-grip the ring for insertion into the chuck.

The back face of the rings is turned in the same operation as facing and boring.

From then on production engineers at the company were involved with the machine tool, tooling and workholding suppliers to continuously refine, develop and 'tune' the production turning process.

VTL Automotive acquired Valeo Transmission (formerly Sagar Richards) through a MBO in November 2001, and the co-operation with Pollard Mori Seiki continued.

Today, VTL Automotive is operating 15 Pollard Mori Seiki machines, having added seven of the Mori Seiki CL-203s to the eight CL-20s production lathes.

A further two machines joined as an in line linked pair will be due for delivery in early 2002.

The latest installation of the CL-203s in Cell 5 is also a linked pair.

It consists of two machines joined in-line to form one cell and is served by a common gantry with two robots.

In operation, the sequence is similar to that of the CL-20s, except that a R”hm double-action chuck grips the ring externally, then internally in sequence.

After machining, one gantry robot places the ring in a turnover device, before the second picks it up and loads it into a collet chuck in the second CL-203 for back end facing and chamfering.

A simple 'handshake' between the two robot controllers is all that is necessary.

The first robot signals to the second that: 'I1ve moved out of the way, you can have it.' The whole 2-stage operation now takes 23 sec, floor-to-floor, and has eliminated the production buffer stocks that were necessary when using two separate operations and machines.

If needs be, the two linked CL-203s can operate as single, stand-alone machines.

Pollard Mori Seiki's and VTL Automotives engineers continue to 'tune' the twin machine cell as well as the machines in the other four cells.

All the tooling, including the tips, are 'specials' supplied locally; no standard tooling is used.

VTL Automotive are very strong on tooling and methods.

Regular tooling investigations are carried out, for example, including Pareto analyses, investigating break-even points between tool life and feeds and speeds, seeking further standardisation in tool types and relating machine and tooling parameters to, for example, surface finish tests.

Efficient cutting of hardened brass is dependent on tool geometry and the avoidance of edge build-up.

To give an idea of the precision machining involved, a typical ring can have an OD of some 80mm, an average wall thickness changing in section from 8 to 3mm and a depth of up to 10mm.

It has teeth and needs to be faced, chamfered, bored and internally threaded.

When being turned, threaded or bored, a ring will try to spring and lobe, but the OEM wants out-of-roundness held within 12 microns.

Individual detail relationships may have to be held within around 5 microns.

To do a job like this in forged and hardened brass, under strict SPC, and achieve near-zero rejects in a batch of 8000 speaks well of VTL Automotives methodology and the quality of the Pollard Mori Seiki CNC lathes.

It also speaks well of the calibre of the machine operators.

In an eight-hour shift, six operators man 15 Pollard Mori Seiki's.

They are totally responsible for quality - there are no formal quality audits - each of five cells are supplied with co-ordinate measuring machines (CMMs) roundness testers and surface quality measurement devices.

'Every operator has his own work specification, they know the CNCs and operate the CMMS as well as carrying out visual inspection,' says David Clegg.

The operators have the backing of a comprehensively equipped standards room, which watch over fixtures/gauges and gauging quality.

VTL Automotive has detailed 32 operators to manage its Pollard 15 Mori Seiki's on a three-shift/24h/5-day basis with overtime and weekend working as necessary.

'We get a very good back-up from Pollard Mori Seiki,' says David Clegg.

'The CNC controllers are a good system, it copes with everything we want of it.

We continually look at other makes of machine, sometimes we even consider other agencies for the same machines, as we always want to know if we are getting the best price.

Overall, both companies have a better than average working relationship.' 'We practice two main philosophies at VTL Automotive,' concluded Bruno Jouan.

'We concentrate on the maximum utilisation of capital and the constant reduction of piece part prices.

Efficient and close collaboration with a machine tool supplier like Pollard Mori Seiki is a major factor in adhering to our philosophies.' On its Luddendenfoot site, near Halifax, VTL Automotive employs 140 of which 100 are directly involved in the production of synchroniser rings and selector forks.

Designed for hard turning use, CNC bar and chucking lathes lift the performance / price index by as much as 30%, in terms of productivity on a very wide range of applications.
Designed for hard turning use, CNC bar and chucking lathes lift the performance / price index by as much as 30%, in terms of productivity on a very wide range of applications. The Hardinge US produced Quest 8/51 and 10/65 models in their SP (Super Precision) execution, could not have been designed to be more suitable for hard turning applications. Developed and built to out perform the heavy duty Conquest T51 and T65 CNC Bar and Chucking lathes, the 8/51 and 10/65 model designations reflect the smaller Quest's 8 in (200mm) chuck size and 51mm through spindle bar capacity (a superb global mixture of units).

With the high value SPC capabilities demanded by more and more customers, on part operations that were previously produced by the grinding process, the Quest SP's specifications and performance meet these demanding requirements exactly.

0.1 micron programmable resolution for positioning and offsetting, on length and most importantly on diameter, enable the SP Quests to produce 5æm tolerance production parts with a Ppk value greater than 1.0.

Another capability with SP resolution is being able to programme out tapers and face geometry errors caused by component deflection, without leaving a significant witness where the correction was made.

Having 10 times as many steps in a combined axis move produces dramatically improved surface finishes, on angles and profiles, compared to conventional, general precision machines with only 1 micron programmable increments.

Other Quest features which all add up to grinding machine performance on hard turning operations are: * Harcrete synthetic granite enhanced vibration damping base construction, providing better surface finishes and longer tool life / lower PCBN tool costs.

* Sub 0.5 micron spindle runouts for improved roundness and concentricity.

* Super finished linear guide slideways for seamless axis reversals, free from stick-slip.

* Hardinge direct seating spindle tooling options for rigidly and accurately locating / relocating parts without distortion.

* linear scale position feedback for the X and Z-Axis minimises warm up periods and reduces the impact of temperature variation in the workshop.

But, that is where the Quest similarities with grinding machines and grinding methods end:- The Quests are all about high speed operation, quick set up and changeover.

A peripheral mount VDI-30 turret, indexing in just 0.1 seconds is the start of a long list of high performance / high speed features and options, to match the Quest machine specification to the work required.

This can equally be a single tool hard turning operation, or a complex multi-tool complete machining process, requiring front and back end work, with or without driven tools Y and C-Axis operations on both ends.

Traverse rates are an impressive 28m/min for the X-Axis and 38 m/min for the Z-Axis and the sub-spindle slide.

The basic Quest 8/51 and 10/65 machines have 4,200 and 3,429 rpm maximum spindle speeds, which suits their universal application for bar and chucking work.

Both the GP Quests and the SP machines have a high speed, high acceleration and deceleration, wraparound main spindle drive option, with 8,000 rpm and 6,000 rpm on the 51 and 65 respectively.

These can be matched to a 10,000 rpm wraparound motor driven sub-spindle, for the ultimate in back end working speed capability.

It is anticipated that these high speed spindle options will be particularly suited for hard turning small diameters and bores, or at the other end of the machineability stakes, for high speed machining on non-ferrous applications.

Overall, the Quest 8/51 and 10/65 in all of their optional configurations are very worthy successors to the Conquest T51/65 machines and lift the performance / price index by as much as 30%, in terms of their productivity on a very wide range of applications.

Pre-machined and heat treated 65HRC gear blanks for aircraft pumps are hard-turned on an Okuma LB300 lathe to an 8 - 12 micron CLA finish in three min instead of 45 min for grinding.
Pre-machined and heat treated gear blanks for aircraft pumps are turned in their hardened state of 65HRC on an Okuma LB300 lathe to an 8 - 12 micron CLA finish in three minutes at the Midlands factory of a leading component supplier to civil and military aerospace programmes. Previously, a grinding machine took three quarters of an hour to remove the same amount of stock - 50 to 75 microns - and leave a similar surface finish. So dramatic have been the savings from hard turning that they have funded the purchase not only of the lathe, but also of a new Okuma grinder to replace an outdated model for subsequent machining of the component after nitriding.

The two machines, supplied by UK agent, NCMT, sit alongside a gear grinder and a cone grinder to form a pump gears finishing cell, which precedes a super finishing cell comprising special lapping machines.

The most important prerequisite for hard turning is a rigid lathe, combined in this case with CBN (cubic boron nitride) tips for machining CPM10V, which is a very hard, crucible powdered metallic material with a high vanadium content.

Part of the turning cycle involves interrupted cutting on the gear faces which precludes the use of coolant, so the journals are dry machined as well for convenience.

In any case when metalcutting with CBN, all the heat goes into the chips so coolant is not needed to control the temperature of the part.

Taking heat out of the component is also the reason behind the manufacturer replacing resin-bonded CBN wheels with the vitrified variety on the new Okuma GA25-T angle-approach grinder, which is equipped with the necessary high pressure coolant facility.

The grinding operation after nitriding previously took 15 minutes on the old grinder to achieve the high surface finish, whereas now the same result is achieved much more quickly, resulting in a further cycle time saving.

In replacing its grinder, the company opted for additional capabilities including continuous rotary dressing to ensure that the wheels are always in good condition.

Specified also was in-process gauging of the gear journals and faces using two separate sets of probes that operate sequentially during the cycle.

Working on the flow line principle rather than as a conventional cell, the system produces two internal gears in batches of six to 12 for about a dozen pump types.

Component size range is approximately 19 to 63mm in diameter, 13 to 51mm gear width, and one to eight inches overall length.

All machines are DNC-linked and component load / unload is manual.

The whole gear manufacturing cell based on hard turning is much more controllable and less skill dependent than the previous arrangement.

Over three days during MACH 2002, two advanced modern apprentices will be battling it out as finalists for the Turning Award trophy and cash prize sponsored by the show organisers.
Over three days during MACH 2002, two advanced modern apprentices will be battling it out as finalists for the Turning Award trophy and cash prize sponsored by the show organisers the Machine Tool Technologies Association (MTTA), in the UK Skill CNC Competition. The two contestants, Adrian Trow of Nickerson Europe based in Wellingborough and Craig Lownie of Weatherford Completion Systems of Arbroath, will have at their disposal two of Colchester's latest Tornado 220 CNC slant bed lathes. These machines are also being shown for the first time at a UK exhibition on the 600 Group stand 5538 in Hall 5.

Each apprentice has 22 hours to complete the set task which involves programming and machining two components, one in aluminium the other in mild steel.

Prior to the start of the competition on Monday 29 April, both aspiring engineers will spend two days at the Colchester Lathe factory training school in Heckmondwike, West Yorkshire, where they will be put through an intensive programming and machine familiarisation course.

This will be followed with a further day's tooling instruction at the plant by Kennametal Hertel.

The test components are complex involving turning, grooving, internal chamber machining and threading.

An important element in the competition will be the ability of the contestants to conform to drawings, dimensions and surface finish requirements while overall presentation will also be gauged by the three independent judges.

The more difficult steel component will account for 60 per cent of the possible marks.

Compliance to main dimensions, which includes tolerances of 21 microns, will make up 50 per cent of the available score for each part.

Two CNC chucking lathes running on very short work cycles have more than lived up to expectations in machining cast cooling system parts for automotive diesel engines.
Two Colchester Tornado A50 CNC lathes running on very short machining cycles have more than lived up to expectations at the West Midlands works of precision subcontractor H L Engineering. Supplied by local distributor Datamach of Coventry, these two chuckers now form the heart of a dedicated production cell set-up last year to machine a family of cast cooling system parts for automotive diesel engines. Combined with a refurbished vertical machining centre, the GBP 110,000 cell handles three different types of stainless steel intercooler component and can machine up to 1,200 castings over two shifts each day.

When planning began for the three machine cell, the company's engineers decided that the two CNC lathes required had to achieve minimal lost time during machining cycles and had track records of high reliability because finished machined castings had to be delivered once a day to the customer's strict Just-in-Time schedules.

As director Robert Laing recalled: 'We looked at several makes of two-axis lathe, but the overall speed, performance, rigidity, track record and value for money of the Tornado package best met our all-round production requirements.' He follows on to recall that as these automotive parts have short turning cycles, the company wanted to keep non-cutting time to the minimum.

'The A50 chuckers had fast acceleration and rapid spindle braking, which were ideal for this sort of work.

We also liked the Fanuc control, as our operators are very familiar with programming this system, and the inclusion of swarf conveyors on both machines was considered an added bonus,' he says.

As part of the Engineering Diamonds Group, H L Engineering is a precision subcontracting company which specialises in the machining of components for the automotive, defence and construction sectors.

Employing 11 people, the Exhall, Coventry-based business has 10 CNC machine tools.

The 5,000ft2 factory is split into two main sections - one for low to medium batch work where batch sizes from one to several hundred are produced and the higher volume area where quantities up to 1,500 a day are machined.

The Tornado cell is installed in the high volume area, near to a vertical machining centre with twin pallets which is mainly used to produce brackets for window systems.

Installed in October 2000, the two Colchester lathes are sited close together and at right angles so that one operator can easily run both machines.

The project involves machining three different 304 stainless steel investment castings, two header components and one gas box.

The turning cycle dominates the cell operation as the twin-pallet vertical machining centre is only used for tapping and chamfering tasks.

Each component requires two main turning operations, one at each end, so the two Tornado A50s are set-up to produce the operations in batched sequence.

Typically, the lathes are run for up to three days on a specific component, in which time between say 3,000 and 5,000 are turned, before being re-set.

All three of the cooling system elements are basically funnel-shaped units measuring 53mm diameter.

The two header components are 23mm long and they feature a flange face on the back end which is tapped and chamfered on the machining centre.

However, the gas box element measures 36mm long and has a main outside diameter which is offset by some 5.7mm.

The turning cycle performed on the headers involve facing, turning, and a boring operation for location.

When the part is reversed, additional facing, counter-boring and chamfering cycles are performed.

Around 1mm is removed from all the machined faces and the total cycle time for each header is 75 seconds.

Similar operations are performed on the gas box, but, a two-jaw chuck is used in order to accommodate the 5.7mm offset of the main diameter.

Narrow recessing operations involve careful removal of some 4mm of material from the neck of the part but still the cycle is very short at 55 seconds.

Tolerances on all three parts have to be maintained at around 0.15mm.

While the speed and performance of the Tornado A50s has enabled H L Engineering to effectively produce all three components, the company has also devised several combined tooling systems in order to further reduce non-cutting time.

Chief production engineer Trevor Weston explains: 'In order to optimise machining efficiency we have tried to limit turret indexing.

On the headers, for example, the first Tornado operations can now be carried out without indexing the turret because two tools are mounted in a single holder allowing us to combine turning and boring.

For header operations on the second machine, we have combined three tools into a single holder, which accommodate rough and finish boring and profile turning.' Combined tooling is also used on the gas box, when three tools are mounted in one holder in order to carry out all the first operation machining cycles.

However, for the second operation the turret has to be indexed one position and with two tools located in one holder, boring and turning are combined.

For the second station, a separate recessing tool is used.

'The use of combined tooling has shaved quite a few seconds from the total machining time,' outlines Trevor Weston.

Coated carbide tooling is used throughout and the operators carry out their own inspection tasks on the intercooler parts with all key diameters inspected 100 per cent.

'But the consistency of machining means there are very few problems in maintaining size or finish.

Concludes Trevor Weston: 'The installation of the two Colchester Tornado A50 lathes has proved to be a highly productive and cost-effective method for machining these cooling system parts.

Both machines have been extremely reliable in service and when there has been the odd minor problem, this has also been sorted out quickly by Datamach, often over the 'phone.'

A compact universal lathe offers exceptional price/performance ratio features and options only previously found in far more expensive machines.
DMG's new compact universal lathe, the CTX 310, offers exceptional price/performance ratio. Despite it entry-level price, it includes features and options only previously found in far more expensive machines. Manufactured by Gildemeister Group company, Graziano, the CTX 310 is designed for the world market and therefore has an impressive range of options to meet customer's individual preference.

It is extremely compact and equipped with a 12-position VDI turret.

With a centre distance of 590mm and a swing of 330mm above the bed, the CTX 310 is suitable for a wide range of universal lathe work.

It is also available with the choice of Siemens, Fanuc or Heidenhain control.

The Siemens 840D control with ShopTurn user interface is particularly noteworthy.

The product of close co-operation between Gildemeister and Siemens, ShopTurn offers the fastest track from drawing to the finished part.

Indeed it sets a new standard in shopfloor programming.

In addition to the control options, the CTX 310 may also be specified with driven tools, chip conveyor, tailstock and a rod machining package which makes this new development attractive for series production.

DMG can also supply the appropriate bar feed to complete the package.

The new CTX 310 complements the successful CTX range by providing a flexible, entry level option.

Thanks to its introduction - and other models at EMO - the CTX range is now one of the widest in the field of universal turning.

Harrison's USA distributor, REM Sales, has recently completed the sale of an Alpha Plus 330S manual/CNC lathe to the River Valley Technical Center, as part of as part of a $300,000 contract.
Harrison's USA distributor REM Sales Inc of East Granby, Connecticut, has recently completed the sale of an Alpha Plus 330S manual/CNC lathe to the River Valley Technical Center, Vermont, as part of a $300,000 contract for new machine tools. The facility, which forms part of the Howard Dean Educational Center, is using the Alpha in support of its comprehensive, two-year manufacturing program that aligns with the NIMS (National Institute of Metalworking Skills) accreditation and certification program. Graduates from the course go on to seek employment in regional firms that focus on small to moderate CNC machining runs or consolidate on their training by pursuing two-year technical degrees.

The contract to supply the lathe and the other machine tools was keenly contested, with River Valley's Manufacturing and Pre-engineering Instructor Chris Gray sourcing nine bids from similar equipment vendors.

The bids were then presented to an advisory committee of local and regional manufacturers and together they selected the best equipment for the future of the program.

Mr Gray comments: 'I participate in a summer internship at a local manufacturer, Lovejoy Tool, each year.

Lovejoy installed an Alpha Plus 400S in 2000 and I have run it and programmed it extensively over the past two summers.

I believe the Alpha was chosen over its competitors because of its 'three-tier' approach to CNC turning: manual with stops, threading and tapers, AlphaLink CAD/CAM system and GE Fanuc control capability.

The quality of the Harrison line was also a characteristic my Advisory Committee gravitated towards.

'To be honest I think that the Alpha is a great machine and my only regret is that as a teacher, I can't seem to find enough time in my day to 'play' with it like I want to.' To date, students have used the Alpha under 'manual' and 'stops' modes only.

However, the CNC curriculum has now commenced, and the course is currently working on aspects of RS232 'G' and 'M' code and manual programming.

The basics of programming are taught for about three weeks before progressing to CAD/CAM.

Students accrue up to 90 minutes experience per day on the Alpha and all have to manufacture 'competency parts' on the machines they are trained on.

The Alpha 'competency part' incorporates a taper, a minimum of three diameters to +/- 0.0005in, a knurl, a thread (Acme, ISO or standard) and at least three length-to-shoulder tolerances that have to be maintained.

The Howard Dean Education Center and River Valley Technical Center not only serve as a secondary technical school for students of high school age, but also house four different post-secondary institutions (University of Vermont, Community College of Vermont, Vermont Technical College and Johnson State Extension Service), who together, could provide an almost unlimited student base with access to the Manufacturing Lab and the Alpha Plus 330S.

The acquisition of sophisticated CNC machinery is a major step forward in machine tool training for the center and support from REM Sales has been 'nothing less than excellent' according to Mr Gray.

Bradley Morris (President - REM), (Barry Ertl - REM sales contact), and Kermit Wright (REM Product Manager), have all contributed to the success of the project.

The Alpha Plus S is an advanced, large capacity two-axis lathe designed for manual, sequential or full CNC operation for almost any batch size.

Control is from an easy-to-use Fanuc console with a twin keypad configuration, providing the operator with the choice of ISO CNC operation from the right-hand keypad and 'AlphaSystem' interactive operation from the left-hand keypad.

The right-hand, ISO keypad has full CNC facilities, utilising canned cycles G70 to G76, tool nose radius and wear offsets, tool path graphics, inch/metric conversion and background editing.

Programs can be entered and/or edited directly at the machine.

The left-hand 'AlphaSystem' keypad is simplicity itself, generating on-screen programmed sequential operations in simple question/answer page format for parallel turning, chamfer, radius, taper and multi-start threads.

The AlphaLink CAD/CAM system is capable of drawing the component and preparing the machining sequences 'off-line'.

Once the machining cycles have been prepared, the program can be saved in either Alpha format or ISO format, both of which can be downloaded to the machine through the RS232 port.

On the River Valley Technical Center project David Smith, Harrison Director/General Manager says: 'I am delighted that River Valley Technical Center has specified the Alpha Plus 330S to help train North America's engineers of the future.

The combined benefits of ease-of-use, advanced functionality, superb build quality and sheer value-for-money have made the Alpha Plus S - and the newly developed Alpha T and U - ideal platforms for teaching basic, advanced and CNC lathe turning skills.

Making its UK debut at Mach 2002 machine tool show is the Hueller Hille Hessapp DVH 450 self-loading, single-spindle, double pick-up turning machine designed to reduce cutting time.
Making its UK debut at Mach 2002 machine tool show is the Hueller Hille Hessapp DVH 450 self-loading, single-spindle, double pick-up turning machine designed to reduce cutting time with optimised cycle times. The model has a built-in grinding facility and is ideally suited to a variety of automotive applications. On show too is a Hueller Hille Diedesheim nbh 95 horizontal machining centre, which offers outstanding machining quality of steel and cast iron products as well as mixed machining of aluminium.

The nbh 95 has an optional capacity of up to 144 tools.

The latest technology in scanning co-ordinate measurement machines will be demonstrated in the form of the Giddings and Lewis Sheffield Endeavor Flexspan machine.

Since a bar-fed CNC lathe was installed, it has operated virtually 24 hours a day with very little manual intervention other than for set-up, bar replenishment and part inspection.
Usually when a machine sits unattended in the corner of a workshop it means that something is not quite right. However, in the case of the Colchester Tornado 'Lights-out' A50 CNC lathe installed by RK International of Erith, at Vire Engineering of Totnes, nothing could be further from the truth. Since the machine was installed, it has operated virtually 24 hours a day with very little manual intervention other than for set-up, bar replenishment and part inspection.

This has firmly established a reputation within the company for consistency, reliability and accuracy and the only complaint from the shopfloor being that there is only one installed.

The south Devon based company is the machining subcontract arm of a small group of companies under the ownership of Mrs Jan Vincent.

One of its principal activities is to produce a range of high quality hose and pipe fittings for motor sport applications from Clubman up to Formula One.

They are supplied to sister company Exact Engineering for distribution as discrete fittings and made-up hose assemblies for brake, fuel, oil and coolant systems.

In addition, Vire also produces precision turned components for defence and aerospace applications.

As Mrs Vincent explains: 'Most of the parts we produce are to established designs which add up to around 2,500 different components made from stainless steel, aluminium, titanium and mild steel.

As part of the production process, many are plated, polished or specialist treated.

Most parts are produced from bar which have a hose attachment at one end and a coupling or banjo union at the other in batches that range between 50 and 2,000.' The company is a long time user of CNC machine tools, particularly for external subcontract machining.

In the past, most of its fittings have been produced using plugboard semi-automatic lathes which were very cost competitive because of the low hourly rate.

This is particularly so on larger batches due to the use of form tools to generate outside diameter profiles.

Les Hutchings, Vire's general manager, comments: 'Accuracy requirements on the couplings range from +/-0.1 mm down to +/-0.025 which was just within the capability of the plugboard machines.

We tended to use CNC for subcontract work but in the run-up to buying the Tornado from RK International we were looking to find a machine that could service both sides of the business.

In practice, the Tornado has proved very productive which we put down to the 'Lights-Out' package supplied with it.' The Colchester 'Lights-out' package comprises the Colchester developed MBF 1000 short bar magazine, Renishaw turret-mounted Tool-Eye probing for tool set-up, an infra-red linked Renishaw touch probe for parts gauging, a parts picker with conveyorised off-load and a swarf conveyor.

The turret has the standard 12 tool stations of the Tornado and control is by a Fanuc 21-Ti system.

However, the machine is different due to the integrated axis torque monitoring, work scheduling software and a sister tool replacement capability.

The MBF 1000 bar feed will hold 12, 40mm bars and up to 10, 65mm diameter bars and is fully integrated with the machine.

This means changeover takes less than 15 minutes to switch say from hexagon to round bar and programming is quick at the machine's Fanuc control due to the dialogue input.

To help control production quantities when running unmanned, each bar is measured by the bar feed system and the number of programmed pieces available from each bar calculated which ensures the machining cycle is stopped when the batch is completed.

'We saw the Tornado as filling the gap between the plugboard machines and our existing CNC lathes.' Les Hutchings explained: 'In practice the unmanned running capability makes it cost-competitive with the plugboard machines as the direct labour requirement is so much lower.

The Tornado provides far more consistent accuracy than the plugboard machines with very little need for adjustment so its proven to be very popular on the shopfloor.' This statement is borne out by Ian Andrews who regularly programs and sets the machine.

'We set the Tornado for batches of 1,000 to 15,000 parts and then do a routine dimensional check every 45 minutes or so.

During the time that the machine has been in use I rarely make any offset adjustments to keep a job in tolerance because the tool monitoring system is so effective and repeatable once the limits are established.' The axis torque monitoring limits are set to replicate empty, worn or broken tools by teach repeat, operator input or by insertion into the part program.

When the critical point is reached the software automatically initiates an immediate stop or sister tool replacement.

At anytime the operator can check look at the screen to see in real time the tool loadings.

Explains Ian Andrews: 'In practice, we use the sister tool replenishment to double up on the roughing tool and small diameter drills and find we get very consistent results in terms of both surface finish and tool wear patterns.

While most jobs are mild steel the Tornado also performs well on stainless steel parts.

It has the advantage of constant surface speed machining while the short bar magazine means we can run at optimum speed at anytime without vibration, so finish is always very good.' Tim Woodward, Vire's assistant foreman points out that due to the single point turning advantage against the plugboard methods, once the tool is initially set the insert can be quickly indexed or replaced in situ and an offset adjustment made.

Because the plugboard machines used form tools they need to be taken-off, reground and re-set.

'Even if there is a spare tool to hand, the changeover process took far longer which means on small batch work we can sometimes set the Tornado and complete the run in less time then it would take to set a part up on the plugboard.' Reflecting the decision to purchase from RK International, Mrs Vincent comments: 'The Tornado has really proven to be cost-effective because it can be left unmanned at night.