Q: For what quantities and component sizes does Swiss turning make economic sense?

Long turning is particularly efficient for small to large series where high repeat accuracy and minimal reworking are required. Automatic bar feeding and multi-channel machining produce components with minimal non-productive times. Prototype production: for production-oriented design for later series production Small and medium series: with flexible tool configuration Large series: with robot-assisted unloading and automatic quality monitoring Economical machining is primarily designed for diameters up to 20 mm and lengths up to 200 mm. Typical applications include precision axles, bolts, sleeves, sensor mounts or valve components where high surface requirements and fitting dimensions are required.

Question 1

What are Long turned parts and how are they technically manufactured using Long turning?

Accepted Answer

Long turned parts are slim, rotationally symmetrical precision components that are manufactured on so-called CNC sliding headstock automatic lathes. In contrast to short turning, Long turning, the workpiece is supported in a guide bush, which is only a few tenths of a millimeter away from the tool during machining. This reduces the tendency to vibrate and enables precise machining of very long, thin workpieces. The process enables simultaneous machining with main and counter spindles, allowing milling, drilling, thread cutting and cross machining to be carried out in a single clamping operation. With multi-channel controls and tool-optimized cutting parameters, components with tolerances of up to ±0.01 mm and surface roughnesses of up to Ra 0.8 µm are created - ideal for high-precision series production. Typical machines are Citizen A20, K16 or L20, which ensure continuous machining even with long runtimes thanks to automatic bar feeders.

Question 2

What materials are used for Swiss-type turning?

Accepted Answer

Long turning covers a wide range of metallic and non-metallic materials. Frequently used: Automatic steels (e.g. 1.0718) - for economical series production with good chip formation Quality steels and tool steels (e.g. 1.7225, 1. e.g. 1.7225, 1.3343) - for high-strength components with thermal stress Stainless steels (e.g. 1.4301, 1.4404) - for corrosion-resistant applications in medical technology and fluid technology Aluminum alloys (EN AW-6061, EN AW-7075) - for lightweight construction and e-mobility components Non-ferrous metals (brass CuZn39Pb3, bronze, copper) - for electrical or precision components with plain bearings Plastics (POM, PEEK, PTFE) - for non-conductive, chemically resistant precision parts For special applications, nickel and titanium alloys (e.g. Inconel 718, Inconel 718, Inconel 718) are used. Inconel 718, titanium grade 5) are used for special applications. Each material requires specific cutting data, rake angles, cooling strategies and tool geometries in order to maximize service life, dimensional stability and accuracy.

Question 3

What accuracies, shape and surface tolerances do modern Long turned parts achieve?

Accepted Answer

CNC sliding headstock turning allows very tight geometric and dimensional tolerances, even with long, slim workpieces. With a temperature-stabilized production environment, ground clamping systems and digital measurement technology, we achieve: Dimensional tolerances of up to ± 0.01 mm Roundness accuracy of less than 0.01 mm Surface roughness up to Ra 0.8 µm (fine machining up to Ra 0.2 µm) Shape and position tolerances according to DIN ISO 1101 Dimensional deviations according to DIN ISO 2768-fine Thanks to inline measuring probes, optical SPC control and adaptive tool compensation, the values remain stable even with long series. For rotationally symmetrical micro-components, process monitoring in real time is also used to compensate for tool wear or dimensional drift.

Question 4

For what quantities and component sizes does Swiss turning make economic sense?

Accepted Answer

Long turning is particularly efficient for small to large series where high repeat accuracy and minimal reworking are required.

Automatic bar feeding and multi-channel machining produce components with minimal non-productive times.

Prototype production: for production-oriented design for later series production
Small and medium series: with flexible tool configuration
Large series: with robot-assisted unloading and automatic quality monitoring

Economical machining is primarily designed for diameters up to 20 mm and lengths up to 200 mm.

Typical applications include precision axles, bolts, sleeves, sensor mounts or valve components where high surface requirements and fitting dimensions are required.

Question 5

How are Long turned parts tested, documented and made traceable?

Accepted Answer

Jedes Langdrehteil durchläuft eine mehrstufige Qualitätssicherung, die bereits während der Produktion greift. Die Prüfung erfolgt inline und offline - automatisiert und normkonform nach ISO 9001 und IATF 16949.Qualitätssicherung umfasst:Maßprüfung durch taktile und optische Messsysteme (z. B. Zeiss Contura 3D, Keyence Optikscanner)Oberflächen- und Rauheitsprüfung gemäß ISO 4287 / ISO 13565Form- und Lagetoleranzen nach ISO 1101Härte- und Gefügeprüfung bei wärmebehandelten WerkstoffenSPC-Prozessdatenerfassung mit automatischem Soll-Ist-AbgleichAlle Messergebnisse werden im CAQ-System gespeichert und chargenbezogen dokumentiert.Auf Wunsch erhält der Kunde Prüfzeugnisse nach EN 10204-3.1 oder Erstmusterprüfberichte (EMPB) für Serienfreigaben. So entsteht ein vollständig digital nachvollziehbarer Fertigungsprozess, der Rückverfolgbarkeit und Auditfähigkeit gewährleistet.

Question 6

What are the advantages of Swiss-type turning compared to other machining processes?

Accepted Answer

Long turning combines high precision, cost-effectiveness and process reliability - especially for slim, rotationally symmetrical components. Compared to short turning or multi-spindle turning, it offers the following advantages: Guide bush principle: stable machining even with length-to-diameter ratios ＞ 10:1 Complete machining: Turning, milling, drilling, tapping and cross machining in one machine Reduced set-up times: Automated tool changes and bar feeding Higher dimensional accuracy thanks to constant clamping ratios Inline measuring systems for reproducible quality This combination makes Swiss-type turning ideal for components with high surface requirements, tight tolerances and recurring series in industries such as automotive, medical technology and mechanical engineering.

Question 7

What design data does a manufacturer need for Long turned parts Manufacturers?

Accepted Answer

Ideally, a drawing, a 3D model and information on the material, quantity, tolerances, surface requirements and test characteristics are required for a reliable technical evaluation of Long turned parts projects. Particularly important are functionally relevant dimensions, fits, thread specifications, roughness values, shape and position tolerancesas well as information on the subsequent installation situation. For Long turned parts in series projects , information on batch sizes, delivery intervals, test certificates, traceability and possible post-treatments are also relevant. This includes heat treatment, surface coating, passivation, deburring, technical cleaning or packaging specifications. The more complete this data is, the more precisely the production strategy, tool design, inspection planning and unit costs for each Long turned parts can be evaluated.

Question 8

Which component geometries are particularly suitable for Long turned parts?

Accepted Answer

Long turned parts are particularly suitable for slim, rotationally symmetrical components with a small diameter, longer length and high dimensional requirements. Typical geometries include shoulders, recesses, axial bores, cross bores, threads, milling contours, flat surfaces or defined functional surfaces that can be machined in a single clamping operation.

Long turned parts such as axles, bolts, sleeves, guide pins, contact pins, sensor holders and valve components are particularly economical. The ratio of component diameter to component length, the required tolerance class, the material, the surface quality and the planned series quantity are all technically relevant. The higher the requirements for concentricity, repeat accuracy and process stability, the more CNC Long turning demonstrates its advantages over conventional turning processes.

Material group	Typical alloys / qualities
Steels & stainless steels	1.0718 (11SMn30), 1.0503 (C45), 1.7225 (42CrMo4), 1.4301, 1.4108
Aluminum alloys	EN AW-6061, EN AW-6082, EN AW-7075
Non-ferrous metals	Brass CuZn39Pb3, copper, bronze, nickel alloys
Plastics	POM, PEEK, PTFE, PA6
Special materials	Titanium alloys, Inconel 718, Hastelloy C-22

Long turned parts