The sixth generation of ultra-high-precision turning centres from the German company Spinner, which started manufacturing them in the 1950s, was launched at the recent AMB 2018 show in Stuttgart.

Available in the UK and Ireland through the Kenilworth-based sole agent Whitehouse Machine Tools Ltd (www.wmtcnc.com), the new Microturn lathe is available in two sizes and can produce components to well within 5µm dimensional tolerance in series production.

To enable this degree of precision, including when hard-turning and micro-finishing components, what Spinner describes as ‘disruptive influences’ from turrets, Y axes and ‘unnecessary’ heat sources have been minimised.

Furthermore, specific design features allow the use of as few axes as possible for any given production process.

The new machine is based on the company’s previous ultra-precision lathes, which have a two-axis spindle head on a compound slide — in this case moving 600mm in X, 350mm in Z — and feature ‘balanced thermal characteristics’ for fine positioning.

The spindle operates in conjunction with a static linear tool carrier integrated into the vertical machine bed (L-version); this not only accommodates turning tools but also heavy special tools such as grinding wheels or high-speed drilling spindles.

Spinner also offers a number of options.These include a BMT45 turret with a ±50mm Y axis and 12 stations that can be added at the bottom of the working area (LT-version).

Even greater versatility is provided by a 15kW 12,000rev/min pivoting B-axis milling spindle with ±50mm of Y-axis movement and an HSK40 interface (LBT-version). It can be served with cutters from a 33- or 72-station tool magazine. There is also an LTBS-version with an opposing counter-spindle (identical to the main spindle).

The Microturn 36 and Microturn 52 lathes (the numbers represent the maximum bar dia-meter) are equipped with in-house-built liquid-cooled motor spindles with ratings of 10.5kW 7,000rev/min (50Nm of torque) and 22kW 5,200rev/min (130Nm of torque) respectively, although speeds up to 10,000rev/min are possible using hybrid bearings.

The chuck diameters are 160mm and 210mm respectively, the swing diameter is 608mm, and the maximum turning length is 250mm.

Control is via the latest version of the Siemens 840D-SolutionLine CNC system, along with a 24in-screen Spinner Touch Panel that is prepared for Industry 4.0 applications.

Robotic workpiece-handling solutions are available for large-series production.