Turning up capacity and capability

17 years later, it is recognised as one of the UK’s leading turned parts subcontractors, something that is largely supported by sliding head turning centres from Star Micronics GB.

In June 2003 RDL began its relationship with Star GB by purchasing its first sliding head machine, an SB-16C. This was followed in 2007 by the installation of a new SR-20RII increasing the company’s turning capacity from 16mm to 20mm.

In 2010, two more Star machines entered the machine shop, a second SR-20RII and a 9-axis SV-20 sliding head. In 2011, machine capacity was again increased from 20mm to 32mm with an SR-32JN and this was followed in 2014 by another SR-32JN together with an SV-32.

This gradual increase in dimensional capacity has now taken another step forward with RDL buying a new Star ST38 machine.

Lewis Lockwood, the production control manager at RDL says: “With 14 Star machines, this acquisition was the next natural step for us as it now gives us capacity up to 40mm diameter. We can carry out multi-axis milling and balanced turning and it’s a lot more powerful than anything else we’ve got in the machine shop.”

Looking at the turret configuration as an alternative to platen tooling stations, Brian Chamberlain, senior programmer at RDL technologies says: “This configuration gives extra flexibility. There are so many different tools and toolholders available for the turret and this allows us to do so many different things such as gear hobbing, gun drilling and polygon turning.

“The machine is something between a sliding head and a fixed head machine. Primarily it’s a sliding head centre with a 350mm stroke on Z1, but it also has a secondary Z3 axis that allows fixed head operation. We also have a JBS flexible guide bush system on the machine which improves the concentricity of the parts being turned.

“With a sliding head machines sometimes, you turn the part and it’s very difficult to go back as the material falls out of the guide bush and you don’t have the traditional support. However, when you have another Z-axis you don’t have that problem. You can turn with Z1 and machine in a conventional manner.”

Referring to the milling capacity of the new ST-38, RDL is machining rectangular support blocks from round bar on the machine as Mr Lockwood explains: “Most people would think that the part was machined on a machining centre, but we can do it on the ST-38.

“Machined from EN16T, which is quite heavy duty, it shows the capability of the machine when machining this high tensile material. On the ST-38, we could machine the job through the night, which makes it more profitable for the company.”

“We have another job that used to be machined on our SR-20II and then finished machined on a machining centre. We can now machine this type of part in a single set-up on the ST-38, saving us considerable set-up and machining time as well as enhancing precision.”

Star GB www.stargb.com