Anyone who wants to work with CNC sheet metal processing is faced with many questions. Be it about materials, tolerances, surfaces or delivery times.
Our comprehensive guide provides you with all the answers: practical, clear and to the point. With our checklist for your perfect inquiry. This will help you find the right offer faster and avoid costly mistakes. Find out now and score points with know-how!
Table of contents
Why targeted research is important for CNC sheet metal processing
In the world of CNC sheet metal processing often only a few details determine the success of a project. Targeted research is not a time waster, but a strategic lever for sustainable decisions in CNC sheet metal production.
Only those who carefully check material requirements, tolerances, quantities and production capacities will find the right partner. And also avoid unnecessary costs or delays. The technological level of the provider also plays a role: modern machines ensure greater precision and efficiency. A thorough market analysis also helps to identify potential savings and shorten the time-to-market.
Smart comparisons give you a clear competitive advantage.
Technical basics of CNC sheet metal processing
Whether prototype or series production - anyone ordering CNC sheet metal parts is faced with numerous decisions. Material, tolerances, surface and CAD data influence costs and quality. Read the answers to important questions about CNC sheet metal processing here.
What is CNC sheet metal processing?
CNC sheet metal processing is a computer-aided process for the precise processing of sheet metal parts. CNC-controlled machines (e.g. laser cutters, press brakes) automatically cut and bend sheet metal.
Milling centers may be used for the mechanical finishing of sheet metal parts - for example for fits, flat surfaces or additional fine machining. In classic sheet metal processing, however, laser cutting, punching and bending dominate.
Compared to the conventional sheet metal processing CNC technology offers clear advantages:
- higher dimensional accuracy,
- Repeatability,
- Shorter set-up times
- more efficient series production.
Because the conventional Sheet metal processing on the other hand, requires many manual or semi-automatic work steps. Even complex geometries can be realized more economically with CNC processing. CNC sheet metal processing is perfect for changing component variants or small to medium quantities in particular.
The automated control system reduces sources of error, minimizes rejects and enables end-to-end digitalization of the production chain. Be it in design or in final production.
For which components and geometries is CNC sheet metal processing particularly suitable?
The CNC sheet metal processing is particularly suitable for the precise production of technical sheet metal parts with recurring geometries. Computer-controlled cutting and automated bending allow complex contours to be produced economically. At the same time, high dimensional accuracy and reproducibility are achieved.
Particularly suitable are:
- Flat sheet metal parts with cut-outs or drill holes
- Edge-molded components with single or multiple bending steps
- Geometries with openings, folds or beads
- Assemblies made from several CNC parts for modular assembly
Typical applications:
- Housing parts and covers
- Mounting plates and brackets
- Panels, angle profiles and supports
- Electronic housings or machine cladding
Advantages for complex geometries:
- High repeat accuracy for series production
- Precise implementation of CAD contours
- Economical production even for small quantities
- Flexibility for design changes or variant production
CNC sheet metal processing is a good solution for components. These components have clear edges, tight tolerances and complex cutting contours. Whether in individual or series production.
What tolerances and accuracies are possible with CNC sheet metal processing?
CNC sheet metal processing offers high dimensional accuracy - crucial for function-critical components and precisely fitting assemblies. Depending on the material, component geometry and manufacturing process, tight tolerances can be reliably maintained.
Typical tolerance ranges:
- Laser cutting: ±0.1 mm to ±0.2 mm
- Punching: ±0.2 mm to ±0.3 mm
- Edging (bending): ±0.3 mm to ±0.5 mm on the angle. Tighter bending tolerances are possible. They often require individual adjustment, bending correction factors in the CAM system or special tools.
- Drill holes & pull-throughs: Up to ±0.1 mm possible depending on the tool
Additional processing steps such as milling or reaming can be integrated for particularly precise applications. This allows Fits, threads or precision mechanical details with even smaller deviations.
Factors that influence accuracy:
- Material type and thickness (softer or thicker sheets can deform more during bending)
- Bending angle and direction
- Machine accuracy and maintenance condition
- Thermal influences for laser cutting
- Springback rate
- Rolling direction of the sheet
Manufacturing companies usually use DIN ISO 2768 (parts 1 and 2). This standard regulates general tolerances for CNC sheet metal parts. However, if required Customer-specific tolerance specifications must be taken into account - especially for prototypes, functional parts or assemblies with high fitting accuracy.
What materials can be used for CNC sheet metal processing?
From prototype construction to series production, CNC sheet metal processing is compatible with a wide range of metallic materials. It therefore offers a high degree of flexibility for different applications. The choice of the right material influences the processing. It also has an impact on the function, service life and cost-effectiveness of the component.
Frequently used materials:
- Steel (unalloyed & galvanized): Robust, cost-effective, easy to weld
- Stainless steel (V2A, V4A): Corrosion-resistant, durable, ideal for outdoor use or hygienic areas
- Aluminum: light, easy to form, high thermal conductivity (preferably from the 5-series, 6-series only conditionally suitable for cold forming.
- Copper: excellent electrical conductivity, ideal for contacts and conductor tracks
Brass: good machinability, decorative, corrosion-resistant - steels specially developed for cold forming
Material thicknesses:
- Typical area: 0.5 mm to 10 mmdepending on the material and processing method. For sheet thicknesses over 5 mm, the bendability should be checked in advance - depending on the machine, tool length and pressing force.
- Thin sheets are particularly suitable for fine cutting contours and small bending radii
- Thicker sheets require special machines, but offer greater stability
Selection criteria for the right material:
- Suitability for cold forming
- Mechanical load (tensile, compressive and flexural strength)
- Corrosion resistance and ambient conditions
Weight specifications for lightweight construction applications - Surface treatments such as powder coating or anodizing
- Costs and availability in the desired quality
The choice of material should already be determined in the design phase. This optimizes production and improves the price-performance ratio.
Which CAD formats can I work with?
For smooth and precise CNC sheet metal production, the Use of compatible CAD file formats crucial. Only with correctly prepared CAD data can sheet metal parts be manufactured efficiently and without errors - from individual items to series production.
Common CAD formats in CNC machining:
- STEP (.step / .stp): Universal 3D exchange format for components and assemblies
- DXF (.dxf): 2D drawing format, ideal for laser cutting, punching and engraving
- IGES (.iges / .igs): Older, but still widely used 3D format for surface and volume models
- SolidWorks (.sldprt / .sldasm): native format from the SolidWorks CAD software
- DWG (.dwg): 2D/3D drawing format from AutoCAD, often used for technical drawings
Recommendation for data transmission:
- STEP files are ideal for 3D manufacturing as they contain machine-readable volume information
- DXF files are ideal for 2D-based processes such as laser cutting or waterjet cutting
- Components should be Clearly defined edges, bending points and material thicknesses be modeled
- Technical drawings with Dimensions and tolerances optimally complement the CAD data
Advantages of compatible CAD formats:
- Faster quotation preparation
- Minimization of queries or errors
- Direct transfer to CAM systems
- More efficient production preparation
A clean database is the key to Short throughput times, High accuracy of fit and reliable CNC machining.
Which surface treatments can be applied retrospectively?
After CNC sheet metal processing, components can be finished with various Surface finishes depending on the area of application, material and visual requirements. This post-processing not only protects against corrosion, but also improves functionality and aesthetics.
Typical surface treatments:
- Powder coating: Resistant coating for indoor and outdoor applications
- Anodizing: ideal for aluminum parts, increases corrosion protection and gives decorative colors, functional: electrically insulating
- Galvanizing: protects steel parts from rust (e.g. galvanized or hot-dip galvanized, centrifugal galvanizing (for large quantities))
- Black finishing
- Varnishing
- Staining, polishing, brushing: for visual enhancement and surface smoothing
- Laser engraving: for permanent marking of type plates or serial numbers
The choice of surface should already be taken into account in the design phase - especially for fits, coating thicknesses or visible parts.
What needs to be considered when designing prototypes and series?
In CNC sheet metal processing, there are Prototypes and Series parts with regard to production strategy, cost-effectiveness and tolerance requirements. A well thought-out design helps to avoid subsequent adjustments and shorten development times.
Important differences and notes:
- Prototypes should be designed to be as production-ready as possible in order to map later series processes
- Series production benefits from standardized geometries, simplified bending steps and optimized unit costs
- Repeat accuracy and process reliability are crucial for series parts
- The following applies to both: close coordination with the paver ensures reduced correction loops
Early design decisions influence production costs, delivery times and later scalability.
How can the design be optimized for CNC sheet metal processing?
A good design is important. It ensures economical and precise CNC sheet metal processing. Errors in the design can cause reworking or production stoppages.
Tips for optimized sheet metal part design:
- Uniform material thicknesses for consistent bending processes
- Observe minimum bending radii (depending on the material)
- No holes or recesses too close to bending edges
- Laser-cutting contours without unnecessary complexity
- Clear tolerance specifications and clean 3D/2D data
CAD files should clearly show bending edges and engravings so that they can be easily transferred to the CAM system.
What minimum bending radii and material thicknesses can be realized with CNC sheet metal processing?
The Minimum bending radii and Material thicknesses depend heavily on the material used, the sheet thickness and the machine parameters. If these limits are not observed, cracks, material breakage or dimensional deviations may occur.
Standard values for bending radii (depending on the material):
- Sheet steel: approx. 1× material thickness
Stainless steel: approx. 1.5× material thickness - Aluminum: 1-2× material thickness, depending on alloy
Material thicknesses in CNC sheet metal processing:
- Typical area: 0.5 mm to 10 mm (For sheet thicknesses over 5 mm, the bendability should be checked in advance. This is because it depends on the machine, tool length and pressing force).
- Thin sheets are ideal for fine laser cuts and complex bends
- Thicker sheets offer more stability, but require higher pressing forces
- Small bending radii may lead to material constraints at the bending point.
Close coordination with the production partner ensures feasibility even with demanding bending requirements.
Are there technical limits or restrictions for complex geometries?
Despite the high precision of CNC sheet metal processing, there are Technical restrictionswhich must be taken into account in the design. Production limits may arise, particularly with complex 3D geometries or very tight tolerances.
Typical restrictions:
- Very narrow bending angles or small radii can cause material deformation (material constraint)
- Deep pull-throughs or narrow interior cut-outs require special tools
- Overlapping bending sequences make clamping and forming more difficult
- Very fine contours <0.5 mm can only be realized with thin sheets and special laser systems. Individual coordination and, if necessary, test samples are recommended here
- High complexity can lead to longer set-up times and higher costs
- If necessary, plan a relief cut at the bending points.
- Observe the minimum bending angle depending on the machine type
Complex geometries can usually be implemented - but only with an adapted design and consultation with production.
How long is the lead time from the CAD model to the first sheet metal part?
The Lead time between the CAD model and the finished CNC component varies depending on the complexity, material availability and capacity utilization of the production partner. With well-prepared CAD data, production can start within a few days.
Typical time periods:
- Simple parts: 2-4 working days
- Complex components with bending steps: 5-7 working days
- Special cases or larger series: up to 10 working days
A structured data import (e.g. STEP + DXF + technical drawing) shortens the coordination process and minimizes queries. Bottlenecks often arise due to incomplete models, unclear tolerances or missing material specifications.
How is quality and dimensional accuracy ensured during CNC sheet metal processing?
Quality and dimensional accuracy in CNC sheet metal processing depend on modern technology. Constant process control is also important. Clear tolerance specifications also play a major role.
CNC-controlled machines offer very high precision. Nevertheless, targeted quality assurance is crucial.
Quality assurance measures:
- Precise machine calibration and regular maintenance
- DIN and ISO standard sheet metal processing
- Random checks during and after production
- Use of digital measuring systems and test gauges
- Documentation of Target/actual comparisons for dimensional check
An integrated quality inspection ensures consistent production results, especially for function-critical components or tight tolerances - even across series.
Which test reports, material certificates or certificates are available?
Depending on the requirements, CNC sheet metal processing can involve various Test documents and certificates are supplied. These are particularly important for safety-relevant components or components requiring certification.
Available documentation:
- Material certificates (e.g. EN 10204 3.1): document chemical and mechanical properties
- Initial sample test reports (EMPB): according to VDA or PPAP for series releases
- Measurement protocols: for documented testing of tolerances and geometries
- Surface protocols: for coated or anodized parts
- Certificates according to ISO 9001 or IATF 16949 (depending on manufacturing partner)
These documents increase traceability, create trust and are indispensable for many industries - such as automotive, medical technology or mechanical engineering. Here you will find all the important test reports and certifications from FACTUREE.
What repeatability and reproducibility does CNC machining offer?
A major advantage of CNC sheet metal processing is the High repeat accuracy - a decisive factor in series production. Thanks to computer-controlled processes and precise tools, identical components can be produced over many batches with minimal deviations.
Factors for high reproducibility:
- CNC machines work with digitally stored processing parameters
- Once programs have been set up, they guarantee constant cutting and bending conditions
- Automated bending and cutting processes minimize operator influence
- Use of Zero point clamping systems and Standard tools for position accuracy
- Permanent Process monitoring and test intervals
Typical repeatability is in the range of ±0.1 mm to ±0.3 mm - depending on the material, component geometry and technology used.
Costs and efficiency of CNC machining
The cost of a CNC-manufactured sheet metal part results from a combination of different influencing factors. The material type, sheet thickness and geometry are decisive. The processing steps are also important. These include laser cutting, edging, drilling and thread cutting.
Added to this are possible post-processing operations such as surface finishing, assembly services or individual test protocols. Set-up times and programming costs for initial sample parts are also included in the calculation.
Price and delivery time are also influenced by external factors. For example, the current capacity utilization of the production plant, the availability of the desired material or special delivery dates. Many manufacturers offer staggered prices or discounts for larger quantities, although there may also be minimum order quantities for certain materials or custom-made products.
In order to create a concrete and reliable offer, we usually
- Complete CAD data (e.g. STEP or DXF),
- a technical drawing with dimensions and tolerances for sheet metal processing,
- The desired quantity and information on material, surface and delivery requirements are required.
The more detailed this information is, the faster and more accurate the calculation can be.
The future of sheet metal processing with CNC: from AI to sustainability
Sheet metal processing with CNC is changing rapidly. Digital technologies, new materials and higher requirements are driving this development. Efficiency and sustainability are particularly important.
This article sheds light on how Artificial intelligence (AI) changed the manufacturing process. He also talks about which Innovations in the area of materials and automation and what to look out for in a resource-saving production must be observed.
How can AI be used in CNC sheet metal processing?
The use of artificial intelligence is fundamentally changing CNC sheet metal processing. AI-based tools analyse CAD data, automatically check feasibility and suggest optimized variants in terms of material and production technology. Also in the Quoting process AI is increasingly being used. Algorithms calculate prices in real time, evaluate sheet metal processing tolerances and forecast delivery times - even for complex geometries or individual items. As with FACTUREE's supplier management tool, for example.
In addition, AI enables the intelligent Monitoring and control of machinesdetects deviations in the production process at an early stage and helps to avoid rejects. In the smart factory of the future, AI will become a central component of the process chain.
What innovations are there in materials and automation?
In parallel with digitalization, materials research is constantly bringing new High-performance materials stand out. Modern sheet grades are characterized by higher strength, better corrosion resistance or improved forming properties - ideal for applications in electromobility, medical technology or lightweight construction.
Also in the area of Automation development is progressing rapidly. CNC machining centers are increasingly being equipped with robot-assisted loading and unloading systems, automated bending cells or intelligent storage systems combined. The result: shorter throughput times, greater process reliability and reduced manufacturing costs - especially in series production.
What is important for sustainable and resource-conserving production?
Sustainability is also becoming a decisive factor in metal processing. One Resource-saving production begins as early as the construction phase - for example through material-efficient design, intelligent nesting of components and the reduction of construction waste.
In addition, the energy-efficient operation of the machines plays an important role. Modern CNC systems have energy management systems that minimize idle times and reduce power consumption. The selection of recyclable materials and the return of offcuts to the raw material cycle also contribute to reducing energy consumption. CO₂ reduction with.
Those who integrate ecological criteria at an early stage not only improve the environmental balance of their production, but also position themselves competitively in the long term - especially in markets with strict sustainability requirements.
Checklist: Guidelines for your optimal sheet metal production
Here is a Compact, practice-oriented checklist with all important questionswhich is a Engineer or technical buyer before the Ordering a CNC precision part from the CNC sheet metal processing should ask. The checklist is systematically structured: from design, material and tolerances to price, quality and delivery time.
| Subject area | Question |
| 🔧 Construction & data | Is a complete CAD file available (e.g. STEP, DXF)? |
| Is there a technical drawing with dimensions and tolerances? | |
| Are minimum bending radii and material thicknesses observed? | |
| Is the component designed for production (laser cutting, edging, punching)? | |
| Are engravings, threads or drill holes specified? | |
| ⚙️ Choice of material | What material is used (e.g. steel, stainless steel, aluminum)? |
| Are there requirements for corrosion protection, strength or weight? | |
| Is a material certificate (sheet metal) e.g. EN 10204 required? | |
| Is the material available at short notice? | |
| 📏 Tolerances: Sheet metal working | What tolerances apply for cutting, bending and drilling? |
| Do the tolerances comply with ISO 2768 or other standards? | |
| Is a test report or dimensional report required? | |
| Is the dimensional and repeat accuracy sufficient for series production? | |
| 🧪 Surface treatments | What surface treatment is required (e.g. powder coating, anodizing)? |
| Are there functional or visual requirements for the surface? | |
| Do edges need to be deburred or polished? | |
| Do you require protective film or special packaging? | |
| 📦 Quantities & scope | How many units are required (prototype, small or large series)? |
| Are there graduated prices or minimum order quantities? | |
| Are assemblies or additional parts supplied? | |
| 💶 Costs & offer | What information is required to prepare a quotation? |
| How is the price made up (material, processing, reworking)? | |
| Are there any hidden additional costs (e.g. set-up costs, packaging)? | |
| Is there a settlement offer? | |
| ⏱️ Delivery time & logistics | How long is the lead time from CAD model to delivery? |
| Are there possible bottlenecks in material or capacities? | |
| Which shipping methods are offered (standard, express)? | |
| Can partial deliveries or call-offs be agreed? | |
| 📄 Quality & Documents | Are test reports, material certificates or certificates available (e.g. ISO 9001)? |
| Is the manufacturing partner certified? | |
| Is there quality assurance during production? | |
| How are deviations or complaints dealt with? | |
| 🔍 Digitization & Support | Are there digital quotation or ordering processes? |
| Is AI used for costing or feasibility checks? | |
| How quickly does communication take place in the event of queries or changes? |
