The installation of two machining centres from Hurco Europe has allowed Lancashire subcontractor AandG Precision to attract more work and produce components more efficiently in fewer setups.

The company is a producer of complex components used in key military and civil aircraft programmes.

It is also active in a number of other sectors, including defence, marine, petrochemical, motorsport, rail and pharmaceutical engineering.

In addition to the batch production of high-precision components, AandG provides a range of additional services, including prototyping, subassembly manufacture and reverse engineering.

One long-running job, an aluminium part, used to be produced in three setups on a three-axis machining centre at the subcontractor's Poulton-le-Fylde works.

The complexity of the component necessitated a lot of step-down profile generation using a ball-nose milling cutter, so overall machining time was around one hour.

The same part has been reprogrammed and is now completed in a single, eight-minute cycle on the company's first five-axis machining centre, a Hurco VMX42SR, which was installed in mid-2008.

There is a large saving in machining time and the two setups are eliminated, considerably reducing the cost of manufacture.

Another component to benefit from one-hit, five-axis, prismatic machining, in this case after a turning operation, is a steel eye bolt that previously required three separate operations on a three-axis machining centre.

The bolt is of relatively simple design, so there is little difference in overall machining time, but two setups are saved.

Michael Pinder, a director of AandG, said: 'Generally, we do not reprogram existing components to run on the five-axis Hurco unless they are ongoing jobs and savings are significant.

'However, the availability of the machine has changed the way we approach the machining of new components.

'In the first year after we started operating the VMX42SR, we produced 73 different parts on it in titanium, aluminium and various steels including stainless.

'A proportion of those contracts we previously would not have won, as the prices for producing them conventionally would not have been competitive,' he added.

He added that the machine was not purchased in anticipation of receiving new contracts, but was bought on spec after a number of customers repeatedly offered AandG five-axis work that it could not fulfil.

Several machines were shortlisted and reviewed at Mach 2008.

One reason for choosing the Hurco was said to be the powerful 36kW/12,000rev/min spindle.

Another was the Ultimax twin-screen control, which includes a special version of the proprietary Winmax software, specifically designed to simplify the programming of complex multi-sided parts.

A further significant factor in the purchasing decision was the swivelling-head design with horizontal rotary table, which, according to Pinder, offers a larger working envelope than the more usual configurations based on a vertical spindle and a two-axis trunnion-mounted table.

In some instances, components are set up in the space at the side of the rotary table on the VMX42SR for second-operation work to be carried out.

At the end of 2008, AandG installed a second Hurco machining centre, this time a three-axis VMX60t with 2m capacity in X.

This was said to be in response to an approach from an existing customer that wanted some ribs machined, knowing that the subcontractor had the necessary ISO 9001:2000 and AS9100 approvals.

The rib contract was limited, but Pinder found that once the machine was installed, its existence on the shop floor created work as soon as customers heard that the facility was available.

Several different jobs approaching the machine's capacity have already been won as a result.

Additionally, some smaller jobs can be fixtured in separate vices on the table to meet demand when the smaller machines are working flat out, so very little time is wasted.

Programming of the Hurco machines is carried out either at a PC in the office running Winmax software or on the shop floor at the Ultimax control.

In the case of the five-axis machine, most programming is done offline as components tend to be complex.

Customers mainly supply Catia models that are converted to STEP files.

Open Mind's Hypermill CAM software converts these into efficient cutter paths that are post-processed and downloaded to the Ultimax control.

The reverse is true of program preparation for the VMX60t.

So far, most has been done at the machine, owing to the simpler nature of the work, with the exception of the ribs.

Pinder said: 'The conversational control [of the Ultimax] is the easiest to use of all our CNC systems and is practically foolproof.

'The operator simply follows instructions on the touch screen, working his way down, filling in the boxes.

'At any point, pressing the "draw" button produces a component graphic on the second screen that shows exactly where he has reached in the program,' he added.

AandG's purchase of the two Hurco machines is part of an expansion programme over the past 18 months that has seen more than GBP1m spent on plant acquisition and buying, extending and refurbishing its previously rented Poulton-le-Fylde premises - a Grade 2-listed corn mill.

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