A complex mild steel gearbox casing, which features external contour machining, several offset bores, an external offset threaded boss and multiple holes, is machined in ‘one hit’.

The name Autoy may be a legacy of the past - the company began by making ‘automatic toys’ some 60 years ago - but this 14-employee subcontractor is very much a business with a future.

And the reason? A continuing investment in new equipment, says managing director Chris Hart, who remembers the company’s first CNC machine being installed in the 1980s when he was serving his apprenticeship.

“Operating manual machines is a good way to learn the fundamentals of metalcutting,” he adds, “but CNC is the only way to go.

We have a flexible, highly skilled workforce but every year makes it harder to find comparable skills.

Most of our CNC machines are Mazaks and if I could go back and do it all again they would all be Mazaks - because they are as easy to program and as easy to use as any CNC machine could be.

This is important, not just because of the skills issue but because customers are very broadly based in terms of location and the type of work we do for them.

However, we are still expected to respond quickly and to satisfy ever more demanding delivery dates.

At one time Autoy’s customers would all have been within a 10-mile radius.

That’s no longer the case and many of the bigger companies who placed regular orders have disappeared.

Where once we would have had a three-month order book, these days it is more likely to be three weeks.

The consolation is that there is a definite lack of subcontractors able to match our capability in terms of value-added machining and fast response, and that is where we concentrate our sales effort.

We invest in new equipment because it helps us get business in the first place, while the quality of our work ensures that we get repeat orders.” Autoy’s latest acquisition is a five-axis 26kW Mazak Integrex 300-IIY turning centre equipped with a tailstock and a high-performance 18.5kW milling spindle.

This milling spindle has X/Z axis travels of 630mm/1.5m and a Y axis travel of 160mm, and is serviced by a 20-tool magazine.

This makes it a genuine multi-tasking machine tool, and one that with its 250mm chuck is ideally suited to the variety of components and materials the Preston, Lancashire subcontractor is called upon to machine.

“We don’t do volume work as such,” says Hart.

“Batches are usually up to 100-off, which means speed is less important than consistency, reliability and ease of setup.

That said, the Integrex is fast - its main spindle speed is 4000 rev/min and it has X and Z axis rapid traverses of 38m/min - and once you get a machine like this you realise what you have been missing.” As with the other CNC machines, programming is undertaken on the shopfloor and the Mazatrol Fusion 640 control’s conversational format is a firm favourite with individual operators.

One reason is that the programming time and length for a complex component such as a gearbox casing for the world’s smallest air tool, used in the assembly of the multi-role Eurofighter Typhoon combat aircraft, are demonstrably less than would be required using EIA/ISO code and programs are easily modified.

And when it comes to repeat business, it’s simply a case of retrieving the cutting conditions stored in the control’s memory and, as Hart describes it, “loading up the tools according to the tool sheet, putting in the offsets and pressing the start button”.

The mild steel gearbox casing, which features external contour machining, several offset bores, an external offset threaded boss and multiple drilled and tapped holes on various faces, is machined in one hit, within a positioning tolerance of 0.0005in.

“We have wiped out all the costs of fixturing for these parts using the Integrex,” says Hart, “and, unlike the previous production sequence, which involved multiple operations and stress relieving, we know parts are sure to be ‘right first time’.” While on a training course at Yamazaki Mazak U K’s Worcester HQ, he says he was like a child with a new toy and couldn’t wait to put the new machine through its paces.

“The Integrex is a big investment for Autoy but it has worked out fine and we have now placed an order for a smaller, one metre z axis travel machine complete with bar feed.” Incidentally, Yamazaki Mazak U K offers an alternative specification machine, the Integrex 300-IISY, with a second spindle in place of the programmable tailstock.

When fitted with a bar feeder and a workpiece puller, shaft workpieces can be produced from raw material to finished part without any manual intervention.

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