Featuring a generous working volume of 815 x 510 x 510mm in a small 2.5 x 1.8m footprint on the shopfloor, the new VC850-5A is the latest prismatic metal-cutting machine to be launched by German machine tool manufacturer Spinner Werkzeugmaschinenfabrik.

The five-axis, vertical-spindle machining centre, which is configured with a +110/-5deg swivelling trunnion carrying the rotary table, is available in the UK and Ireland through sole sales and service agent Whitehouse Machine Tools, Kenilworth.

Managing director Tim Whitehouse said: “This is a top-end machine with robust rotary axes, which are normally the weak point in five-axis machining. They are driven by a new planetary gear train and are fitted with absolute rotary scales instead of incremental encoder feedback.

“We are also impressed by the additional clamping plate beside the table that allows Op20 as well as Op10 to be programmed into a single cycle for one-hit machining. The option of a rotary hydraulic supply for automatic workpiece clamping is a further benefit, as it introduces the possibility of automation for long periods of unattended production.”

The five-tonne machine has an FEM-optimised, cast construction that provides a high level of rigidity and vibration damping for elevated cutting performance and high standards of surface finish on machined components up to 200kg. Further advantages are that tool life is extended and accuracy of machining is enhanced.

Part of the reason for the machine's compactness is the patented method for protecting the saddle's Y-axis guideway from swarf and coolant ingress using a single wiper system, eliminating the need for a telescopic cover.

The depth of the machine is consequently shorter, leading to a 30% reduction in the area needed for installation. The X-axis guideway also has a single wiper, allowing the table to move to the extremes to simplify automated loading and unloading from the sides.

Powerful, high-speed spindle options are 12,000rpm SK40/BT40 or 18,000rpm HSK63, both rated at approximately 18kW and offering 86 and 57Nm of torque respectively. They are served by a 32-pocket tool magazine, although a 48-station version is available. Rapid traverse in all linear axes is 40m/min to minimise non-cutting times.

High pressure coolant delivery at 22 or 70 bar may be specified to assist chip-breaking when cutting difficult alloys and to encourage swarf evacuation, which is in any case assisted by two spiral augers feeding the chip conveyor.

Further choices are in-cycle workpiece and tool measurement, mist extraction, various tooling packages, and linear scales to replace the rotary encoders on the large-diameter ballscrews in the orthogonal axes, providing absolute positional feedback to match that of the rotary axes.

The Spinner VC850-5A is equipped with the latest generation of Siemens control, Sinumerik One, which features software for the creation of a corresponding digital twin of the machine.

Technology functions help improve processing speed, contour accuracy and workpiece quality. In the second quarter of 2021, the option of a Heidenhain TNC620/TNC640 control will be available.