Award for Innovative Lathe

At the MWP Awards Dinner held in Birmingham, UK, on April 22 during the MACH 2008 machine tool exhibition, Geo Kingsbury Machine Tools won the category "Best Metal Cutting Machine Tool (Turning)". The Award was for the INDEX SpeedLine C-Series of mill-turning centres and was collected on the night by Bill Hawkes, Sales Director of Geo Kingsbury, the sole agent for INDEX machines in the UK.

The reasons for the German-built machine range being selected as the winner by the panel of eleven independent judges was, in their words, "Absolute flexibility and accuracy, vast cycle time reductions - a very rigid concept - it's good to see a machine tool manufacturer challenging convention".

The latter comment referred to the innovative turret drive, which uses two interconnected steel plates sliding directly over the machine bed to replace the conventional compound slide. The critical advantage is that the distance between the turret centreline and the point at which it is driven is much shorter. The turret and drive plates are fitted with ceramic-coated, hardened tool steel strips at top and bottom which slide over a third plate of surface-hardened cast iron fitted into the bed, the latter plate being effectively sandwiched between the other two.

This and other design features have allowed INDEX to create a machine tool with a high resonant frequency which is over twice as stiff, ie rigid, as the established INDEX G-series models of equivalent capacity. Induced vibration is minimised, so there is more latitude for finding the 'sweet spot' for any combination of toolholder, cutter and workpiece material, allowing depth of cut to be increased for maximum metal removal rate.

Photograph shows the INDEX C-Series sliding-plate replacement for the conventional compound turret slide.  The kinematic drive is behind the bed, to the right.