A success story of productive bar and chuck machining

The automatic production lathe INDEX C100 is one of the most successful CNC production lathes. This machine has set industry standards in terms of productivity, damping, rigidity and tool lives. The design of two Y-axes opposite each other has given the user an enormous productivity boost to minimize cycle costs. In particular, the two or three tool turrets traversing independently from each other for machining on the main and counter spindles increase the efficiency. The automatic production lathe has a spindle clearance of 42 mm. The customer can choose between a Siemens or Fanuc control.


The INDEX SingleSlide guide system has proved itself with excellent results in the field. The tool slide for the X and Z motions only consists of a single piece and moves the turrets on surface sliding guides instead of roller guides. This means the tool carriers 1 and 2 slide on guides that are securely bolted to the machine bed. The virtually wear-free sliding pair consists of full-hardened mild steel plates (guides) and coated sliding elements (tool carriers). Precise adjustment ensures absence of backlash between the gliding elements. This design combines the familiar benefits of sliding guides, such as good damping properties and high rigidity, with acceleration and rapid traverse performances that so far had been implemented in machine tools only on the basis of linear roller guides. The drive concept is an innovative double scissors kinematic design that is responsible for the low thermal growth and high accuracy of the machine. The small masses to be moved allow accelerations up to 1 g.

Three tools being used simultaneously

Three tools being used simultaneously

The INDEX C100 meets the market demands of manufacturing ever smaller workpieces from hart-to-cut materials according to ever increasing requirements for accuracy. Also, the increasing complexity of the workpieces requires a growing number of tools to be used. As a solution, all three turret heads are equipped with 14 tool mountings according to DIN VDI 69880-20. For users who prefer to continue using existing tool holders according to DIN VDI 69880-25, the turrets are optionally available with 10 tool stations. The INDEX W-serration and an INDEX-specific, enhanced VDI interface ensure setup repeatability of +/- 8 µm even for angled tools – and that at a distance of up to 100 mm from the tool mounting device.

Flexible Y-axis 2x on the main spindle or 1x each on the main and counter spindles

Flexible Y-axis 2x on the main spindle or 1x each on the main and counter spindles

Low secondary times and thus further cycle time reductions are the result of fast rapid traverse rates of up to 60 m/min in the counter spindle’s Z-axis. The vertical machine bed provides for unhindered chip flow. Noticeable is also the very good sealing of the working area. The machine has a fully closed enclosure with a height-adjustable control panel. The offset control cabinet allows quick and easy access from the rear of the machine for servicing. Removing the sheet panels opens up free access to the drive kinematics and to the entire electrical and hydraulic installation. A major benefit for both operators and setup personnel is also how easily the INDEX C100 can be set up thanks to its exemplary accessibility to the working area. The fact that this compact automatic lathe only has a minimal footprint is something that can be expected from an INDEX machine.

INDEX SingleSlide –  an innovative guide system

INDEX SingleSlide – an innovative guide system

Besides highly productive bar machining, the automated material handling for chuck and shaft parts needs to be mentioned for the fast automatic production lathes. An integrated workpiece handling unit with an external pallet station automatically supplies chuck or shaft parts to the machine. A swing/gripper arm places the machined parts onto a conveyor belt or on dedicated pallet stations. The automated handling of pre-machined parts not only increases productivity but also allows integration into chained systems.

Applications of the automatic production lathe INDEX C100 include all major industries that require complex turned parts, such as automotive supplies, fittings & fluid engineering, and medical technology. Since its market introduction, the C100 has proved that in terms of performance such as acceleration, dynamics, achievable rapid traverse rates, and drive power of the main and counter spindles, it’s hard to find anything comparable.


Source INDEX-Werke GmbH & Co. KG