Measurement and control specialistACI (UK) reports that 2006 was an

excellent year for Acu-Rite and AnilamCNC sales – a volume increase of 43 percent above 2005, some 24 per cent aheadof budget.

While company managing directorPhil Goulding says CNC upgrades andretrofits still account for around 25 percent of its CNC sales, he adds: “There isalso no doubt that an increasing numberof users are buying new rather thanrepairing very old equipment.”

CNCs are becoming faster and morepowerful than ever due to technologicaladvancements in the field ofmicroelectronics. An increasing numberof integrated functions simplify even themost complex machining processes.These products are also becoming moreuser friendly, not only in their

programming, but also in other ways,such as ease of installation and ease ofmaintenance.

HIGH PERFORMANCE MACHINESSeries 30i CNC products by GE Fanuc canbe used in high performance machinessuch as revolving transfer machines,complex mill-turn centres and multi-functional machines that requiresophisticated and exceptionally quickfunctions, multi-channel capability andmultiple axes that can be controlledsimultaneously. Up to 40 axes can beinterpolated on the Series 30i CNC, 24 ofwhich can run simultaneously. Up to 10channels are available.

The control unit also contains a newultra high speed processor, an internalhigh speed bus for a transfer capacity 10times greater than that of current CNCs,

extremely rapid current control, a pulsegenerator that produces 16 millionpulses per rotation and nanometreinterpolation for all contour movements.

Siemens is also keen to push theboundaries of what can be achievedusing the latest CNC technology. Forinstance a colossal 5-axis Henri Linégantry-style machining centre hasrecently been upgraded to a state-of-the-art machine tool capable ofmachining carbon composite wing sparsdestined for use on the new AirbusA400M military transport aircraft.

Located at the GKN Aerospacefacilityon the Isle of Wight, the machine is nowusing SINVCS, a new Siemens productthat consists of a Sinumerik 840D CNCcontrol system allied with volumetriccompensation algorithms developed bythe University of Huddersfield, toachieve positional accuracy of 0.05mm(the diameter of a human hair) or betteranywhere within the operational volumeof this 25 m x-axis machine!

Alan Myers, technical director at theCentre for Precision Technologies withinthe University of Huddersfield’s Schoolof Computing and Engineering, explainsthe significance of the data: “On most 5-axis Cartesian machining centres, thelinear/rotary positional accuracy of eachindividual axis is usually quoted by the

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www.machinery.co.uk ● March 2007

Clever New ControlsCNC and DRO manufacturers are

reporting climbing sales. Steed

Webzell investigates the reasons

why and discovers that increased

functionality heads the list

CNC/DRO

Newall’s 2-axis B60 DRO solved a problemfor sub-contractor RS Tooling, which fittedit to its large DSG Type 30 centre lathe

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machine’s manufacturer, say ±0.01mmfor example. The relevant ISO or DINstandard is also quoted. But thisinformation only relates to linear/rotarypositions in a single axis. In reality, thereare over 40 error sources that can allcontribute to the inaccuracy of variouspositions within the machine’s volume.To only quote five figures is arguablymisleading. However, the standards areslowly moving towards volumetric error.I believe ISO now calls for a diagonalcheck. End users are also beginning tobecome more aware of the need forvolumetric accuracy, particularly theaerospace sector, where largecomponents and assemblies areprevalent. Based on laser measurement,in our own cutting trials we have able todemonstrate a 97 per cent improvementin volumetric performance.”

The next step is volumetric thermalcompensation – a fraction of the cost ofa temperature controlled environment.

Elsewhere, Heidenhain’s iTNC 530control’s existing functions, whichinclude exact tool guidance with 5-axismachining, simple tilting of the workingplane and high contour accuracy forHSM, have now been complemented bya TNCGuide help system; Adaptive FeedRate control; global programmingsettings; expansion of the DXF converter;and enhancement of smarT.NC toinclude tool tables, expanded filemanagement and programming duringa program run.

ACI (UK)’s new Anilam 6000i boastsa highly intuitive user interface and newsolid modelling capabilities that enableusers to manipulate (cut, section, rotateand measure, for example) 3D graphics.

Solid model graphic representationsof canned cycles are another centralfeature of the system. For instance,graphics visually interpret, in real time,all changes/commands as relevant datais being entered. 2D graphics are alsoprovided.

RETROFIT DROSSome manufacturers simply do notrequire CNC technology. For themretrofit DROs continue to be thefavoured option.

For example, having previously beenadvised that it was not possible to fitDROs to its Gleason Bevel Gear cuttingmachines, Smiths Aerospace ofWolverhampton was pleasantlysurprised when Heidenhain specialistDRO retrofitter IMEK Precision proved

that it was. Alex Phelps of Smiths Aerospace

explains: “Set-up of bevel gear cutters istime consuming and involves setting upto six axes, including rotary axes, linearaxes and axes that move in an arc. Evenwith experienced operator/setters, thisoften took two days.”

IMEK’s solution was Heidenhain’sPOSITIP 888 multi-axis display used inconjunction with a mix of rotary andlinear encoders. Linear and rotaryencoders were fitted to the top andbottom offsets, top and bottom spaceangles, cutter cones and root angle. Asecond Heidenhain readout, an ND780,aids setting root angle and depth.

Another DRO success story is told bySouthampton-based sub-contractmachinist RS Tooling. It has just acquireda Newall Measurement Systems’ B60two-axis DRO for use on a large (120 inbed, 48 in swing) Dean, Smith & GraceType 30 lathe.

Repeatability was a key factor in theselection of the B60. “One job, a spindlefor a robotic crane, features nine journalsalong a 1,400 mm length,” explains co-owner Tony Clark. “All of the journals runto within 0.02mm, with ±0.02mm onthe diameters. A relief is also requiredbetween each journal. Using the B60 thiskind of job is made so much easier –previously we would have been countingthe turns of the handle.” ■■

� Enter 180 atwww.machinery.co.uk/enquiry

CNC/DRO

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March 2007 ● www.machinery.co.uk

Plain English and user friendly CNCs for XYZ

At XYZ the common denominator in controls is user friendliness, whether they bethe latest generation ProtoTRAK CNC fitted to bed/turret mills and ProTURNlathes, or the Siemens 810D ShopMill and ShopTurn CNCs fitted as standard toXYZ machining centres, bridge mills, turning centres and large capacity lathes.

According to Nigel Atherton, XYZ Machine Tools’ managing director: “Weselect controls for our machines based on two main criteria. First, it must be thebest control available for the production task in hand. Second, it must be easy touse.” And he cites the ‘plain English’ programming procedures at the heart ofboth ProtoTRAK and the Siemens ShopMill and ShopTurn controls as an idealway to reduce set-up times, shorten lead times and lower labour costs.

5-axis machining made easy withHeidenhain’s iTNC 530

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