Big capacity route to five-axis machining

For the latter half of its 16-year existence, Sheffield-based contract machining firm Ian Cocker Engineering has relied almost exclusively on Hurco vertical machining centres to produce prismatic components, mainly for the oil and gas sector. Now, to extend its capacity, the company has installed its first five-axis model, a Hurco VMX84SWi. The machine is the largest in the manufacturer’s VMX range and the first to be installed in the UK.

Proprietor Ian Cocker says: “The large working envelope means we can machine parts that we previously had to turn away. We produce them cost effectively, as the machine has an integral B-axis spindle head and we’ve added a fifth CNC axis by purchasing a Kitagawa rotary table.”
In 2014, volume production for the oil and gas industry accounted for 80% of the subcontractor’s turnover. That figure halved due to the slowdown in the sector. Luckily, much of the shortfall was replaced by development contracts in the same field, while additional work was won from the AMRC at Sheffield University, and from Sheffield Forgemasters.
A batch of components for the latter customer was one of the first jobs to be put on to the VMX84SWi. The project involved re-engineering seven rack segments, measuring 1 m long, for the axis drives on a Chinese-built floor-type milling machine in use at Sheffield Forgemasters. Each segment required 40 teeth to be machined at an 11° angle to an accuracy of ±15 µm.
“Having a B-axis on the big machining centre was ideal for completing this job as it avoided having to tilt the components to mill and chamfer the teeth,” says Cocker.
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