With C axis and 12 driven tools, a three-axis slant bed CNC lathe offers users a level of single set-up turn/mill/drill capability that is unparalleled on a cost-to-performance basis.

With C axis and 12 driven tools, the Taiwan Takisawa EX-308 three-axis slant bed CNC lathe now available from Ward CNC of Sheffield offers users a level of single set-up turn/mill/drill capability that is unparalleled on a cost-to-performance basis. Coupled with the use of a heavy-duty cast iron bed that promotes powerful and stable operation, the machine's four-track super rigid precision linear guideways and high-speed servo turret combine with the Fanuc 21iT CNC to provide users with an exceptional 'Japanese quality at Taiwanese prices' package. With a swing over the bed of 450mm, the EX-308 has a between centres distance of 645mm and a maximum turning diameter and length of 260mm and 530mm, respectively.

The 52mm bar capacity machine has rapids of 20/24m/min and a spindle speed of 30-4,000 rev/min from the 11/18.5kW motor.

Driven tools speeds are 40-4,000 rev/min.

Auto tool setting arm and parts catcher are standard, and the use of the optional auto toolsetter, bar feed and robot interface systems can significantly enhance the machine's capability for the unmanned production of complex parts.

Twin-spindle twin-turret CNC lathe fitted with a robot part-loading system has transformed a general subcontractor into a world-leading brand in the mountain bike aftermarket.

Hope Technology chooses Nakamura for productive one-hit machining A combination of enthusiasm and innovation has helped Hope Technology transform itself from a general subcontractor into a world-leading brand in the mountain bike aftermarket. As part of its long-term manufacturing focus Hope has recently invested in a Nakamura-Tome WT-150 twin-spindle twin-turret lathe supplied by Turning Technologies. The new machine, which is fitted with a robot part-loading system, is part of Hope's drive for continuous improvement of its processes - with the emphasis on high-quality, repeatable and productive one-hit machining.

Simon Sharp and Ian Weatherill, the co-founders of Hope, started their careers as apprentice toolmakers at Rolls-Royce and went on to set up their own subcontracting company.

They had always been interested in motorcycle trials riding and mountain bikes, so after a few years in business it is not surprising that they turned to making what interested them.

'We could see that the technology on a trials bike was eventually going to be applied on a mountain bike and saw an opportunity,' says Sharp.

'We made a front hub first, went to a few mountain bike races and it took off from there.' Hope now makes and markets a range of hydraulic disk brake systems for mountain bikes, as well as stand-alone hubs and other ancillary equipment.

'A lot of the mass-produced products on the market are cast, but we believe that machined parts are stronger, better balanced and more attractive - all our hubs are machined from billet,' says Sharp.

As well as quality, Hope is also focused on process improvement by reducing production times, handling, and the number of operations.

'That is why we bought the Nakamura WT-150,' says Sharp.

'We are making 30,000 to 40,000 hubs a year and we will now be able to do them in one go rather than two operations as we were doing it before.

This is our first twin-spindle twin-turret machine, but we needed both turrets because there is a lot of machining on both ends of the part.

With twin turrets we can balance the operations to get the best cycle time.' He explains that as well as turning, drilling, tapping and de-burring, each hub calls for a significant amount of milling, making the Y-axis a necessity.

'We are literally starting with a billet and ending up with a finished part that can go straight into anodising.

It has cut out a lot of dead time,' he says.

It takes about 7-8 minutes to produce a hub so the robot is standing idle quite a lot of the time, but it is still cost-effective because there is no downtime and no need for an operator to keep loading parts.

But to automate effectively it is vital to have the right machine tool to build the system around, and Simon says it was Nakamura's good reputation for quality and process stability that led him to decide on the WT-150.

'It is a machine designed for production, and what we really like about it is that it is very accurate.

We do not have to adjust the offsets very often and the repeatability is very good.

That is important to us.

We talked about putting probing on the machine, but realised that we did not really need it.

If you are going to adopt unmanned running you need to be sure that the process is very stable.' Before deciding on the WT-150 he looked at a variety of other ways of doing the job, including a vertical lathe loaded with billets.

The problem there, he says, was that you have to have turnover stations and it can get quite complicated when you try to locate the second side.

Sharp also looked at a gantry loading type of machine, but that was quite an expensive option and not as flexible as using robot loading on the Nakamura.

'With the WT-150 you do not have to worry about locating the part as you are loading a plain billet and the machine knows the orientation it is in when you transfer it between spindles,' he says.

For the hubs the robot is loading cut billets.

65mm diameter and, as Sharp points out, if you wanted a barfeed machine to cope with this diameter it would have to be a big machine.

'A bar-fed twin-turret machine to do this job would have to be a pretty big piece of kit and a lot more expensive as well.

And once you start having to turn bar that size all the spindle speeds start to get much slower.

Multi-tasking CNC mill/turn centre has the ability to fully utilise 3D-CAD, offers utilisation of linear guides in all axes and allows 0.0001 degree increments to be programmed on the B- and C-axis.

Yamazaki Mazak's Integrex range, the most widely sold multi-tasking machine tools in the world, epitomise the Done in One concept, with components machined complete in a single set-up. Now, with the introduction of the Integrex Series IV, this concept is further advanced. The fourth generation Integrex series provides the user with a powerful multi-tasking machine tool platform from which to make full use of the machining flexibility that Yamazaki Mazak has created.

One of the key developments on the series IV Integrex machines is the introduction of the Mazatrol Matrix control.

It is this new CNC system that enhances the capabilities of the machine and the interface between it and the operator and/or remote production management and control.

Features such as Intelligent Safety Shield would not be possible without the development of the Matrix control system.

Typical of the range is the all-new Integrex 300-IV ST, which makes its UK exhibition debut at MACH 2006.

Key among the developments of the series IV Integrex is the ability to fully utilise 3D-CAD, utilisation of linear guides in all axes, and 0.0001 deg increments on the B- and C-axis.

This, when combined with the exceptional rigidity of the machine design, results in even better positional accuracy.

The Integrex 300-IV to be displayed at MACH features opposed spindles and a lower turret with driven tool capability, capable of working on either spindle.

Using the lower turret and upper tool station simultaneously for balanced cutting greatly reduces cycle times, improves turning accuracy and delivers higher quality in terms of surface finish.

Additionally, thanks to the innovative design of the lower turret, the same tool can be used to machine components located in either of the two spindles.

This reduces the total number of tools required, reducing tool costs and improving productivity.

Other developments across the Integrex range include Intelligent Thermal Shield, Intelligent Safety Shield and Active Vibration Control.

Intelligent Thermal Shield has been developed to minimise heat displacement, the machine units producing the minimum possible amount of heat during operation.

Additionally, there is automatic compensation for changes in room temperature.

As a result, machine heat displacement is less than 10 micron with a room temperature change of 8 deg C.

Intelligent Safety Shield highlights any possible collision points when any program is simulated on-screen prior to it being used to actually machine components.

However, Intelligent Safety Shield takes this protection several steps further with the machine being monitored when it is operated in manual mode for instance, during tool measurement with the Tool Eye or when changing inserts.

All machine movements are monitored by the Mazatrol MATRIX control, which moves the machine's 3D model simultaneously with the manual data inputs to check machine interference.

Should this occur, the axis movements are stopped immediately, preventing damage to the machine and avoiding costly downtime.

The third innovation is Active Vibration Control, which reduces vibration in all axes during rapid accelerations and results in improved accuracy and surface finishes.

The main specifications of the Integrex 300-IV are a maximum machining diameter of 760mm; maximum machining length of 1524mm; 26kW, 4000 rev/min turning spindles; 18.5kW, 12 000 rev/min milling spindle; and rapid traverses of 38m/min in X/ Z and 26m/min in Y, with a maximum C-axis rotation speed of 555 rev/min.

Richard Turner reports that misconceptions about sliding head automatic lathes mean companies are missing out on the productivity and cost benefits of multi-turret fixed head machines.

In the past few years we have seen more and more parts in the smaller size range produced on 25 to 32mm capacity sliding head machines. These machines are designed to produce long slender components - and for that type of part nothing can beat them. But people have run away with the idea that they are designed for all types of small turned parts.

For most parts above 20mm in diameter, and for many smaller parts too, a fixed head, multi-turret machine may be able to make them in half the time with less waste.

The reason for this is that, with one or two exceptions, the fixed head machine manufacturers have neglected this size range and left the field wide open to companies offering sliding head machines.

In the last couple of years Nakamura has moved to redress the balance by introducing fixed head machines specifically designed for the highly productive manufacture of small components.

Nakamura initially introduced the WT-100, a 42mm capacity machine specifically designed for producing parts down to less than 10mm.

It has two turrets, a Y-axis on the top turret, twin spindles for simultaneous machining of first and second operations - and a lot more power than a sliding head machine.

With up to 7kW on the driven tools and 11kW on the spindles we can use modern tooling technology to its utmost potential and really attack cycle times - literally halving them in many cases.

More recently, the company introduced the Super NTY3 twin-spindle machine - with three driven-tool turrets, each with Y-axis machining.

This means that up to 96 tools are immediately available, including 36 driven tools, for simultaneous cutting with three tools.

You've not just got two turrets that are truly flexible to either spindle, you've now got a third turret that can work between the spindles as well.

So with three Y-axis turrets you have a unique and absolutely flexible capability.

The cycle time improvements are not the only reason for choosing fixed head machines.

The beauty of the sliding head machine is that the part is supported by a bush, so the tool is cutting right up against the bush, which means it is very rigid when you are producing shaft-like parts.

But once you have fed the material through the bush you can't go back to it - so you generally have to produce the finished diameter in one pass.

That means that you have to compromise on the cutting conditions.

If you are going from 32mm down to 5mm, yes you can do it, but you may have to use lower feed rates and this will lead to problems with swarf.

This is why the fixed head machine is so much better on the majority of turned parts.

Another cost advantage of the fixed head machine is that there is no need to use high-quality bar as raw material because it is being held in a conventional chuck rather than passing through a precision bush.

There is also a lot less waste.

On a fixed head machine the waste at the end of a 3m bar is literally the length of the component and the grip length of the collet, whereas on a sliding head machine you can lose up to half a metre of material per three metre bar.

That's maybe not such an issue at the smaller sizes, but it can be on larger diameters, and when you are working in expensive materials such as brass.

Given these lower operating costs, combined with the lower capital cost of the Nakamura machines, 'UK turning' can add substantially to its 'bottom line'.

* About the author - Richard Turner is with Turning Technologies UK - distributor for Nakamura-Tome high precision turning centres and CNC lathes.

Aero engine rework companies ar are buying standard vertical turning lathes - built from modules - and tailored to suit the requirements of this specialised market.

Webster and Bennett International - based in Warwick, UK - is building standard and customised CNC vertical turning lathes from 1000mm to 2500mm diameter capacity. Using standard modules, the company can offer very simple or very advanced, 'tailor-made' machines at attractive proces. The company also builds a universal vertical turning, machining and grinding centre - a very cost effective product.

In the very busy aero engine rework sector, companies are already buying Webster and Bennett standard machines tailored to suit the requirements of this market.

Second rams for grinding - built into the CNC swivelling saddles, are one new benefit.

Another innovation allows eliptical turning.

* About Webster and bennet International - Webster and Bennet is a daughter company of the Ogepar group, which has manufacturing and trading companies throughout Europe and Africa.

The group includes Pegard Productics, Balliu, ABC Diesels - both based in Belgium - and KBB in Dresden, Germany.

pegard productics builds very large, precision horizontal boring and milling centres.

Balliu builds laser machine tools while ABC Diesels build marine diesels, locomotive power units and power generators.

KBB manufactures turbochargers.

Webster and Bennett has achieved success - 13 orders - in the German market and orders from UK, Belgium, The Netherlands, Canada and Egypt.