EDMs Using the flexibility of the Internet for remote access and machine management of its nine wire EDMs will give a subcontractor very effective communication with the machines' control systems.

Blantyre (Glasgow)- based Scottish specialist spark erosion machinist, The Spark Erosion Centre, is set to take its adoption of EDM technology to new heights and harness the availability and flexibility of the Internet for remote access and machine management of its nine Fanuc Alpha Robocut wire EDMs. At a stroke the adoption of this method of working will enable very effective communication with the machines' control systems to manage events and see in real-time the exact state of production affairs and, when appropriate, enable corrective action to be taken. 'This development will springboard our company even further ahead of the competition,' maintained co-director Bill Brynes, 'And it will be particularly useful when the machines are running unmanned at night and over weekends, as is usually the case.' It is no coincidence that the battery of Fanuc Alpha wire cut machines underpins The Spark Erosion Centre's established reputation for the responsive supply of cost-effective wire eroded parts to a wide range of customers throughout the UK.

The company has just installed its ninth machine, a Fanuc Robocut Alpha 1-iC with a 410mm Z-axis and extra large work tank to extend its capacity for larger work.

According to proprietor David Gilbert: 'The progressive installation of Fanuc machines has been maintained because they prove to be very reliable, represent value for money and, importantly, have always produced the high-class components we have demanded.

Over the years we've never been shy about investing in the latest Fanuc technology from 600 Centre to enable us to cut faster and to work smarter and better.' Working smarter is definitely the way to describe the addition of the remote access using the Internet, to which Brynes added: 'Having the ability to remotely interrogate each control system will be indispensable when, for example, a machine is working unattended on large capacity workpieces.

These can be up to 300mm thick, and cycles sometimes demand a week of non-stop cutting.

Without such access, we could easily lose a weekend's production if there is a fault and the machine stops,' he said.

The conviction that Internet access is the ultimate in harnessing unmanned control of a machine is further evidence of how the Scottish team has never shied from harnessing the latest wire erosion technology to gain production benefits.

With its roots stretching back 25 years to the manufacture of mould and press tools - an activity it continues today - the company's use of the spark erosion process has continually evolved in tandem with machine developments.

This has been taken advantage through a progressive investment strategy in more powerful and more capable machine installations that have been subsequently traded-in for the latest machines with even more advanced features.

'We have come a long way from the early punch-tape controlled units,' said Brynes, 'And we have a track record of being early adopters of, for example, machines with automatic wire feed and submerged cutting as well as the progressive development of increased cutting speeds.

Program management for all our Fanuc Alpha machines is based on a PC network, which will be fully utilised when our plans for Internet access are finalised.' The three latest installations at The Spark Erosion Centre of two Fanuc Alpha O and the recent larger capacity 1-iC Robocut from 600 Centre of Shepshed near Loughborough typify the level of performance-seeking technology currently available from the company's wire cut stable.

With the latest machines The Spark Erosion Centre is able to cut at rates up to 330mm2/min using 0.3mm brass wire and carry out a fully automatic wire feed while submerged on work pieces up to 100mm thick inside 12s.

By using thermal melting this is some 20s faster than the previous generation Fanuc machine.

The thermal melting extends the reliability of the machine through a much simpler process and the annealing effect of the heat generated improves wire straightness and creates a very sharp edge at the point of cut.

With thermal melting wire disconnection takes just four seconds and reconnection eight seconds and the process eliminates any need to drain and refill the tank.

The Robocut Alpha-1i features Fanuc FS 180is-WB 5-axis control and the latest TR1600 non-electrolysis power supply.

This prevents surface corrosion on the parts and, by reducing the heating effects on the re-cast layer of the material being processed, the surface does not soften around the cutting area.

Indeed, surface roughness better than 0.08 micron Ra can be achieved using the micro-finish power supply In addition, with the latest AI corner control, wire deflection is minimised giving more precise path control that is important to The Spark Erosion Centre to ensure maximum profile and corner accuracy.

Indeed, with the latest machines, advances in the technology means they are capable of holding roundness to within 1.2 microns on a 30mm hole.

Latest machine enhancements also overcome problems when cutting into an edge of a workpiece, for instance, which leads to wire breakage and subsequent delays.

This is often caused through an unstable dielectric supply that can also oxidise the surface of the component.

Both these problematical areas are overcome with the latest Fanuc A1 Cut-in function that automatically adjusts cutting conditions and dielectric fluid pressure.

As a result, each entry into a new cut is smooth and stable.

Once in the cut, the Fanuc Nano Interpolation software is able to distribute positioning commands from the NC control with a pitch of 0.001mm (one nanometre) to each of the axis servomotors.

As these are fitted with ultra-high resolution 16 million pulse coder feeds, any accumulation of axial movement error is eliminated thus maintaining a very precise and smooth feed rate.

* Latest adaptive control software - the latest adaptive control software is able to detect any changes in workpiece thickness and automatically adjusts the process settings to maintain cutting efficiency and thus avoid wire breakage.

This feature can improve cutting speeds by up to 30% at the Blantyre company compared to conventional methods.

With similar cutting rate, control and generator capabilities, the Fanuc Robocut can accommodate workpieces weighing one tonne and handle a 16kg bobbin of wire giving some 125h unmanned running when using 0.2mm diameter wire, 80h with 0.25mm wire and 55h with 0.3mm wire.

Multiple operations in a single set-up on multiple-loaded parts, and the machines' control technology, were both highlighted by Brynes as being especially useful.

'While multiple loading enables us to make maximum use of the working area of each machine, the control functionality provides us with a precise insight into cutting speeds and cycle times.

This means we can price each job very accurately,' he said.

Like their stablemates on the 19-employee company's 10,000ft2 site, the Fanuc Robocut Alphas are kept busy producing a varied mixture of parts in predominantly 316 stainless and Inconnels as well as brass, bronze and other exotic materials.

Quantities span single parts to batches of perhaps 100 or more for a wide range of clients across the oil industry, aerospace and electronics sectors.

Workpieces can include very thin parts, since the wire erosion process imparts no forces, as well as very intricate electrodes from tungsten copper, parts for sporting guns and components from solid billets, with both external and internal blends and curves.

The shopfloor is also home to spark erosion and toolmaking sections, as well as a battery of plastic injection moulding machines that offer a trade moulding capacity as well as own-product manufacture of the likes of caps and spacers, to the construction industry.

'Our business is all about customer service,' concluded Gilbert.

'We really do not know what will come through the door next, so having the variety and flexibility of the nine wire erosion machines gives us the resource to be able to respond quickly with high-calibre parts at the right price.

That is what our customers want - and, indeed, it is exactly what we want from our suppliers.' He continued: 'That is why we've always returned to 600 Centre for wire edm as well as a Joemars 325DZ EDM drill.

The level of service provided by 600 Centre has always been impeccable, and in our world of sub-contract supply where customers place increasingly demanding requirements on component complexity, delivery and price, having that comfort factor is indispensable.' But, he reacted: 'Our customers' demands remain as stringent as ever'.

'Even if they continue to move the goal posts we know that by using machines of the calibre of the Fanucs, we will remain at the top of the league.'