Long turning

CNC Long turning is a high-precision machining process for long, slim components with complex geometries. The workpiece is supported on a rotating sliding headstock automatic lathe (Swiss-type) via a guide bush close to the cutting edge. This means that even delicate components with a large length-to-diameter ratio can be machined without vibrations.

During machining, the main and counter spindles take over the workpiece fixture, allowing the front and rear sides to be machined simultaneously. Modern multi-channel controls allow parallel tool movements in the X, Y and Z directions. This produces rotationally symmetrical precision parts with tolerances of up to ± 0.01 mm and surface roughnesses of up to Ra 0.8 µm. The process is ideal for series production in the Automotive, medical technology and sensor industries and offers maximum process reliability thanks to complete machining in a single clamping operation.

Our long turning production covers almost the entire spectrum of machinable materials. These include free-cutting and heat-treatable steels (e.g. 1.0718, 1.0503, 1.7225), corrosion-resistant stainless steels (1.4301, 1.4404, 1.4108), aluminum alloys (EN AW 6082, 7075), as well as non-ferrous metals such as brass CuZn39Pb3, copper or bronze.

For demanding applications, we also machine nickel and titanium alloys (e.g. Inconel 718, Titanium Grade 5) as well as high-performance plastics such as PEEK, PTFE, POM or PA6. Each material requires individually adapted cutting values, tool geometries and cooling strategies in order to achieve optimum chip formation, tool life and surface quality.

With tool-specific parameters (cutting speed Vc, feed rate f, rake angle γ) and temperature-controlled cooling, we ensure dimensionally accurate long turned parts with minimal distortion and excellent surface structure - reproducible across entire series.

Thanks to state-of-the-art CNC sliding headstock turning centers with hydrostatic guides, thermally compensated axes and ground clamping devices, we achieve dimensional tolerances of up to ± 0.01 mm and form and position tolerances in accordance with DIN ISO 1101. Depending on the machining step, the surface quality is varied by cutting speed, tool radius and feed rate and is typically Ra 0.8 µm, with fine machining even up to Ra 0.2 µm.

Inline measuring probes and optical inspection systems monitor every machining step. Closed-loop control automatically compensates for tool wear, temperature drift and material fluctuations. This ensures that the process capability (Cp / Cpk) remains constant even with high quantities.

Our measurement technology includes tactile measurement, 3D coordinate measurement and optical profile scanners for documentation in accordance with ISO 4287. This means that even the tightest geometric specifications can be reliably met.

Long turning is suitable for all batch sizes - from pre-series to large series of over 100,000 pieces (depending on the component geometry). For small series, CAM-based CNC programs (Inventor, Esprit) enable complex 3D geometries to be implemented quickly.
For higher quantities, automated bar feeders and robot cells take over the material feed and removal, enabling unmanned shifts to be implemented around the clock.

The combination of multi-channel control, counter-spindle machining and simultaneous milling operations reduces reclamping processes and significantly shortens cycle times.

The result is economical production costs per unit with maximum precision.
Thanks to consistent process optimization and productive maintenance systems, machine availability remains at a very high level, which brings decisive cost advantages, especially in series production.

Every manufactured part is subject to a multi-stage quality inspection. After each production step, dimensional, shape and surface parameters are checked in accordance with ISO 4287, DIN EN ISO 2768 and DIN 50150.


3D coordinate measuring machines (e.g. Zeiss Contura) are available for final inspection. B. Zeiss Contura), optical measurement projectors, roughness measuring devices and hardness test benches are available for final testing.
All measurement results are recorded digitally in a CAQ system and documented in a fully traceable manner using batch numbers. Test reports in accordance with EN 10204-3.1 are generated automatically and linked to serial numbers.

For customers in the automotive industry, auditing is carried out in accordance with IATF 16949 with SPC (Statistical Process Control) evaluation. This quality concept ensures that every long-turned part meets the specified requirements - transparently, auditable and reproducible right up to the final traceability.