Laser Cutting and Punching

The maximum thickness depends on the type of material and the power of the laser used. Most commonly, steel up to 20 mm, stainless steel up to 15 mm, and aluminum up to 12 mm are cut. For thinner sheets, the laser offers extreme precision and a clean cut, while for thicker materials, it is necessary to choose the appropriate power and type of laser (e.g., fiber or CO₂).

For thinner sheets, laser cutting provides high precision, clean edges, and excellent repeatability. As material thickness increases, the process requires higher laser power, optimized cutting speeds, and the appropriate assist gas. The choice between fiber and CO₂ laser technology is therefore made according to the material, thickness, required cut quality, and production requirements.

Yes, laser technology enables highly accurate cutting even for complex shapes. Thanks to 2D and 3D lasers, it is possible to process not only flat sheets, but also spatial parts, tubes, and profiles. The laser beam moves with high precision according to a digital model, making it possible to produce even complex geometries with minimal tolerance without the need for additional machining.

The correctness of the material is ensured by an automated warehouse system that is directly connected to the production machines. Thanks to this connection, only material approved according to the order requirements reaches production, eliminating the possibility of mix-ups.

Laser cutting is one of the most precise, flexible and efficient methods for sheet metal processing, but like every manufacturing technology, it also has certain limitations. The suitability of laser cutting depends mainly on the material, sheet thickness, required edge quality, part geometry, production volume and the subsequent manufacturing operations.

One limitation is the relationship between material thickness and cutting speed. Laser cutting is extremely productive for thin and medium-thickness sheet metal, while processing thicker materials generally requires more laser power, lower cutting speeds and higher consumption of cutting gases. For very thick plates or applications where extremely high cutting accuracy is not required, other technologies may sometimes be more economical.

Laser cutting is also a thermal cutting process. The concentrated laser beam heats the material locally until it melts or vaporizes, which creates a heat-affected zone along the cut edge. With correctly selected parameters this effect is very small, but it cannot be eliminated completely. Depending on the material, thickness and cutting conditions, minor discoloration, oxidation, burr formation or changes to the cut edge may occur. Components with particularly demanding functional or visual requirements may therefore require additional machining or surface finishing.

Another factor is the type of material. Different metals absorb laser energy differently and therefore require different laser sources, cutting gases and process parameters. Modern fiber lasers are particularly effective for processing steel, stainless steel and aluminum and can also process reflective non-ferrous metals such as copper and brass when the appropriate technology is used. HTP combines fiber and CO₂ laser technologies, allowing the cutting process to be selected according to the material and application.

For some high-volume applications involving a large number of identical holes or standard geometries, CNC punching can be more economical than laser cutting. Punching uses physical tooling and can produce repetitive holes and certain formed features very quickly. Laser cutting, on the other hand, offers significantly greater flexibility because changing the component geometry normally does not require manufacturing a new physical tool.

The operating costs of laser cutting must also be considered. These include electrical energy, cutting gases, consumable components and regular maintenance of the optical and cutting systems. However, modern automation can significantly improve overall manufacturing efficiency. At HTP, laser machines are integrated with an automated STOPA material storage system, helping to streamline material handling, improve machine utilization and reduce unnecessary manual operations.

For this reason, the most economical solution is not determined by the laser alone. At HTP, laser cutting is integrated into a complete manufacturing chain that can include CNC sheet metal bending, machining, welding, surface finishing and assembly. This makes it possible to optimize the complete component rather than only the individual cutting operation.

A CNC punching machine is a computer-controlled sheet metal processing machine that produces holes, cut-outs and other geometrical features by mechanically pressing a punch through the sheet into a corresponding die. The position of the sheet, the selected tool and the punching sequence are controlled automatically by a CNC system.

Unlike laser cutting, where the contour is created by a focused laser beam, punching is a mechanical process. The machine uses interchangeable punches and dies with defined geometries. The sheet is accurately positioned underneath the punching head and the programmed features are produced one after another according to the digital manufacturing data.

CNC punching is particularly effective for sheet metal parts containing a large number of repetitive holes, slots or standard shapes. Once the appropriate tooling is available, individual punching operations can be performed extremely quickly. This makes the technology attractive for serial production of components such as enclosures, covers, electrical cabinets, brackets, panels, ventilation components and structural sheet metal parts.

Another advantage is that punching machines can perform operations that conventional laser cutting cannot perform in the same way. Depending on the machine and available tooling, punching can be used not only to separate material but also to create certain formed features directly in the sheet. These may include embossments, louvers, countersinks or other functional geometries. Several manufacturing operations can therefore be incorporated into a single production stage.

The main difference between CNC punching and laser cutting is flexibility. A laser can follow almost any programmed two-dimensional contour without requiring a dedicated cutting tool for that geometry. This makes laser cutting highly suitable for complex shapes, prototypes, small batches and frequently changing components. Punching requires suitable physical tooling, but it can be extremely productive where the same geometries are repeated many times.

The two technologies can therefore complement each other. In sheet metal fabrication, the optimal process is selected according to part geometry, material thickness, required production volume and subsequent operations. Combined punch-laser systems take this principle even further by combining the productivity and forming capabilities of punching with the geometrical flexibility of laser cutting within one production system.

There is no single universal tolerance that applies to every laser-cut component. The achievable laser cutting tolerance depends on several factors, including the type and thickness of the material, component dimensions, geometry, laser source, cutting speed, cutting gas, thermal conditions and the required quality of the finished edge.

Modern CNC laser cutting machines are capable of very high positioning accuracy and repeatability. In practical sheet metal production, dimensional tolerances are commonly measured in tenths of a millimeter, but the tolerance that can actually be guaranteed for a specific component must always be evaluated according to its drawing and manufacturing conditions. Thin sheet and simple geometries can generally be produced more accurately than very thick material or components containing long, narrow or thermally sensitive features.

It is also important to distinguish between machine positioning accuracy and finished-part tolerance. The accuracy specified for the movement of a CNC machine does not automatically represent the dimensional tolerance of the finished component. The final dimensions can also be influenced by the width of the laser kerf, heat input, material flatness, residual stress in the sheet, material composition and the behaviour of the component after it has been released from the surrounding sheet.

Material thickness is an important factor. As thickness increases, the cutting process becomes more demanding and cutting speed, laser power and gas parameters have a greater influence on the quality and geometry of the cut. The same numerical tolerance therefore cannot automatically be guaranteed for a thin stainless-steel cover and a thick structural-steel component.

At HTP, different laser technologies are available for different production requirements. The TRUMPF L5030 6 kW fiber processes sheets up to 1500 × 3000 mm and is specified by HTP for steel up to 20 mm, stainless steel up to 15 mm and aluminum up to 10 mm. The TRUMPF L5030 5 kW fiber also processes sheets up to 1500 × 3000 mm and is specified for steel up to 25 mm, stainless steel up to 15 mm and aluminum up to 10 mm. The TRUMPF L3030 3.2 kW CO₂ is specified for steel up to 20 mm, stainless steel up to 12 mm and aluminum up to 8 mm. The appropriate machine and cutting parameters can therefore be selected according to the material and component requirements.

For components requiring especially tight functional tolerances, laser cutting can also serve as the highly accurate initial manufacturing stage followed by CNC machining of critical surfaces, holes or other dimensional features. This combination makes it possible to use the productivity of laser cutting while achieving tighter tolerances where they are functionally required.

For this reason, the required dimensional tolerances should ideally be specified directly in the technical drawing. HTP can then evaluate the material, thickness, geometry and subsequent production processes and select the most appropriate manufacturing method for the component.