CNC Machining of Parts with Angled Surfaces – What Affects Machining Accuracy?
Angled surfaces are found in many mechanical components, from simple planes to more complex geometries that must be precisely positioned relative to other features of the part. In such cases, not only the dimensions of the surface matter, but also its orientation relative to the specified datums. CNC machining of such components requires proper workpiece positioning, stable clamping and a carefully planned sequence of operations. Even a small error in workpiece referencing can result in angular deviations and affect subsequent assembly or the interaction between components. Why Are Angled Surfaces Challenging in CNC Machining? When technical documentation specifies a surface at a particular angle, its correct position relative to the rest of the geometry must be maintained. The challenge becomes more complex when a component contains several surfaces positioned at different angles or when tool access is limited. In such cases, CNC machining may require additional setups or a different toolpath strategy. In our work, we pay particular attention to which surfaces are used as references for the specified angles and which features will be functionally important in the finished component. It is also important to determine whether an angled surface will serve as a mounting surface, a datum or a contact surface. This determines how strictly its position must be controlled and inspected after machining. How to Prepare a Workpiece for CNC Machining of Angled Surfaces Process preparation begins with an analysis of the technical documentation. The manufacturing engineer determines which surfaces can be used as datums, the order in which individual features should be machined and whether the cutting tool will have sufficient access to the machining area. Every change in workpiece setup can introduce additional deviations. Therefore, it is important to minimise the number of repositioning operations and plan the machining sequence to maintain the required geometric relationships. Workpiece Referencing and Positioning Properly selected machining datums provide reference points for subsequent operations. If a component is positioned incorrectly, even a precisely machined surface may end up at the wrong angle relative to the rest of the part. For this reason, CNC machining accuracy depends not only on the machine tool itself but also on how the workpiece is located and clamped. Stable positioning improves repeatability and reduces the risk of errors in subsequent operations. From our experience, analysing the entire sequence of operations during process planning is particularly important for components with more complex geometries. We discuss this in more detail in our article “From documentation to stable production – the work of a technologist at SIM Gdynia“ Tool Accessibility and Machining Sequence Not every angled surface is equally accessible to the cutting tool. Restrictions may result from the depth of the component, adjacent walls or limited space around the surface being machined. In such cases, selecting the right CNC machining strategy and determining the order of operations are essential. Some features should be machined earlier, before subsequent operations restrict tool access. Tool length and diameter are also important. Excessive tool overhang can reduce system rigidity and increase susceptibility to vibration, affecting both surface quality and the accuracy of the machined angle. What Affects the Accuracy of Angled Surfaces? Even minor deviations occurring during CNC machining can affect the final geometry of a component. Important factors include positioning accuracy, tool wear and cutting stability. This is particularly important when a surface must maintain a specified position relative to holes, other planes or mounting features. Therefore, not only the angle itself matters, but also its relationship to the remaining geometry. Clamping Rigidity and Component Geometry The workpiece must remain securely clamped throughout the entire operation. If cutting forces cause movement or deformation, the resulting angle may differ from the value specified in the technical documentation. The risk increases with slender components, thin walls or limited clamping surfaces. In such cases, the workpiece support and clamping method should be adapted to its actual geometry. We discuss similar challenges in more detail in our article “CNC Machining of Thin-Walled Components – How to Reduce Vibration and Deformation?“ Tool Selection and CNC Machining Parameters Tool type, geometry and overhang affect cutting stability and the quality of the finished surface. Machining parameters should be selected according to the material, component design and clamping method. Overly aggressive CNC machining parameters can increase vibration and tool loads. On the other hand, excessively conservative settings do not always provide the best balance between quality and production time. In our work, we evaluate cutting parameters together with component geometry and technical documentation requirements rather than treating them as a separate part of the process. How to Inspect Angles and Surface Positioning After CNC Machining Inspection of the finished component should not be limited to checking basic dimensions. If the technical documentation specifies the orientation of surfaces relative to other features, the required geometric relationships must also be verified. At SIM Gdynia, we have more than 800 measuring instruments, allowing us to adapt inspection methods to the geometry and tolerances of each component. The key is to evaluate measurement results against the datums specified in the technical documentation. For more demanding components, it is important not only to measure the angle itself but also to verify whether the surface is correctly positioned relative to the remaining geometry. Summary CNC machining of components with angled surfaces requires careful consideration of workpiece referencing, clamping stability, tool accessibility and machining sequence. Each of these factors can affect the final position of the surface relative to the rest of the component. A properly planned process helps reduce the risk of errors, maintain the required accuracy and ensure repeatability across successive parts. This is particularly important for components where angled surfaces serve mounting functions or interact with other elements. Are you planning to outsource CNC machining of components with challenging geometries? Contact us and send us your project documentation.
CNC Machining of Parts with Deep Pockets – What Challenges Arise During Production?
Deep pockets are found in many mechanical components, including housings, bodies, plates and structural parts. Machining them may seem like a straightforward milling operation, but as pocket depth increases, so do the requirements for tooling, process stability and effective chip evacuation. CNC machining of such components requires careful process planning. Key factors include pocket geometry, tool overhang, cutting parameters and the ability to maintain stable machining conditions throughout the entire pocket depth. Why Are Deep Pockets Challenging in CNC Machining? The deeper the pocket, the more difficult it becomes for the cutting tool to reach the machining area. Tool overhang increases, system rigidity decreases and chip evacuation from the bottom of the pocket becomes less effective. All these factors can affect surface quality and the dimensional accuracy of the finished component. With over 45 years of experience and a machine park comprising more than 100 CNC machines and devices, we also manufacture components whose geometry requires longer cutting tools or several consecutive operations. In such cases, CNC machining requires more than a suitable program. A carefully planned toolpath strategy and the correct selection of cutting parameters are essential. The ratio between pocket width and depth is also important. The narrower and deeper the pocket, the greater the risk of process instability and difficulties accessing corners and the bottom of the component. Most Common Problems When CNC Machining Deep Pockets When machining deep pockets, production challenges can affect both the cutting process and the quality of the finished component. Their significance depends on factors such as component geometry, material properties and the selected CNC machining strategy. In practice, two areas require particular attention: maintaining stable cutting conditions and ensuring effective chip evacuation. Problems in these areas can occur simultaneously, so both should be considered during process planning. Vibration, Long Tool Overhang and Reduced Surface Quality Long tool overhang reduces rigidity and increases susceptibility to vibration. This can result in poorer surface quality, uneven machining marks and difficulties maintaining the required dimensions. In more severe cases, vibration can also accelerate tool wear or cause tool damage. Therefore, when planning CNC machining operations, it is important to keep tool overhang to the minimum necessary and adjust cutting parameters to the actual operating conditions. A similar problem occurs when machining thin-walled components, where the rigidity of the entire setup directly affects process stability. We discuss this in more detail in our article “CNC Machining of Thin-Walled Components – How to Reduce Vibration and Deformation?“ Chip Evacuation and Coolant Access to the Cutting Zone As pocket depth increases, effective chip evacuation becomes more difficult. If chips remain in the cutting zone, they may be recut, scratch the machined surface or interfere with tool operation. Limited coolant access to the bottom of the pocket can make the problem even worse. As a result, cutting temperatures increase and machining conditions become less stable. From our experience, simply increasing coolant flow is not always sufficient when machining deep pockets. Toolpath strategy and the proper distribution of successive cutting passes are equally important to prevent excessive chip accumulation. How Does Deep Pocket Geometry Affect CNC Machining Preparation? Component geometry largely determines how the machining process should be planned. Important factors include not only pocket depth but also width, corner radii, bottom geometry and tool accessibility. Before production begins, the manufacturing engineer must assess whether the entire geometry can be machined using a single tool or whether the CNC machining process needs to be divided into several stages. Corner Radii, Pocket Depth and Width Small corner radii require tools with appropriately small diameters. However, as tool diameter decreases and tool length increases, rigidity is reduced, which can negatively affect cutting conditions. For this reason, pocket geometry should be analysed as a whole. A very deep pocket with small internal corner radii may require several tools: a larger one for removing most of the material and a smaller one for finishing corners and hard-to-reach areas. Tool Selection and Cutting Parameters Tool selection should take into account the component material, pocket depth, surface quality requirements and chip evacuation conditions. Tool diameter, cutting length and overall tool overhang are also important. CNC machining parameters must be adapted to these conditions. Overly aggressive settings can increase vibration and tool loads, while excessively conservative parameters do not always provide the best results in terms of production time. In our work, we select machining strategies based on the entire setup: component geometry, material, tooling and the capabilities of the specific machine tool. Only by considering these factors together can a stable process be achieved. How Can Deformation Be Reduced While Maintaining Component Accuracy? Removing large amounts of material from inside a component during CNC machining changes its stress distribution and rigidity. Depending on the geometry, this can lead to minor deformation during or after machining. The risk can be reduced by planning the correct sequence of operations, leaving sufficient material allowance for finishing passes and removing material evenly. Proper workpiece clamping is also important, as it should not introduce additional stresses. From our experience, separating roughing and finishing operations often produces better results for more demanding components than attempting to achieve the final dimensions in a single stage. This allows the workpiece to stabilise before the final passes and improves the chances of maintaining the required accuracy. Inspection and Repeatability of Components with Deep Pockets Deep pockets can be challenging not only to machine but also to inspect. Limited accessibility may make it difficult to measure the bottom, side walls or dimensions located deep inside the component. For this reason, inspection methods should be considered during process planning. Depending on the requirements, different measurement techniques may be used, with particular attention paid to dimensions and surfaces that directly affect the functionality of the finished component. At SIM Gdynia, we have more than 800 measuring instruments, allowing us to select appropriate inspection methods for the geometry and requirements of each component. You can learn more about our approach in the article “Quality Control in CNC Machining
How to Reduce the Risk of Component Damage Between CNC Machining Operations
Manufacturing a component in accordance with technical documentation does not end when it is removed from the machine. During production, the component may be transported, set aside, inspected, clamped again, or transferred to subsequent processes. Each of these stages involves a risk of damaging previously machined surfaces. Even a small scratch, dented edge, or damaged thread can cause the component to no longer meet the requirements. That is why CNC machining involves not only performing each operation correctly, but also handling the component properly between operations. Where Does the Risk of Component Damage During CNC Machining Come From? As production progresses, more and more finished surfaces, holes, threads, and edges appear on the component and must be protected against accidental damage. The source of the problem does not have to be the CNC machining itself. Damage can occur while setting the component down, when two parts come into contact with each other, during transport between workstations, or when the component is clamped again. Residual chips can also be a problem, as they may leave marks on a previously finished surface. From our experience, the way a component is protected should be treated as part of the entire production process, especially for parts with high quality requirements. At Which Stages of CNC Machining Is the Component Most Exposed to Damage? The risk appears primarily when the component changes position or is transferred to the next workstation. For this reason, when planning the process, it is worth taking into account how the part will be moved and set aside. Transporting and Setting Components Aside Between Operations Between successive stages of CNC machining, direct contact between transported components should be limited. Placing several precisely machined parts directly on top of one another can lead to scratches, dents, or damaged edges. The storage method should be adapted to the geometry and weight of the part. Depending on the component, containers, separators, or specially prepared storage areas may be used to protect the most important surfaces. Workstation cleanliness is also important. A single chip left behind may be enough to leave a mark on a finished surface when a heavier component is placed on it. Inspection, Assembly and Additional Technological Processes A component can also be damaged during dimensional inspection, assembly, washing, or when being transferred to subsequent technological processes. Reference surfaces and functional surfaces require particular attention. Damage to them can affect not only the appearance of the component, but also subsequent operations, assembly, or the performance of the finished part. How to Protect a Component Between CNC Machining Operations Not all surfaces are equally exposed to damage. The protection method should therefore depend on the geometry of the component, the requirements in the documentation, and which operations have already been completed. The key is to determine which surfaces require special protection during support, clamping, and storage of the part. Protecting Machined and Reference Surfaces Surfaces that have already been machined to the required tolerance should be protected during subsequent CNC machining stages. This applies especially to surfaces with specified roughness requirements and reference surfaces used for subsequent setups. Damage to a technological reference surface can affect the positioning of the component during the next operation. A scratch on a functional surface, in turn, may require additional inspection or rework. In our work, we adapt the way a component is stored and transported to which surfaces have already been finished and what requirements they must meet until the end of the process. Protecting Edges, Holes and Threads Edges and threads are particularly vulnerable to mechanical damage. An impact during transport can dent an edge or damage the first turns of a thread, making later assembly more difficult. Protecting holes against chips and other contamination is also important, especially in the case of internal channels. You can read more about machining and inspecting threads in the article: “CNC Machining of Threaded Parts – How to Avoid the Most Common Threading and Thread Inspection Errors?”. How Does Process Organization Affect Component Safety After CNC Machining? Reducing the risk of damage should not depend solely on operator care. The organization of the entire process matters, from designated storage areas and transport between workstations to the storage of parts waiting for the next operation. In serial production, it is important to apply the same rules to all components. Proper arrangement and separation of parts reduces the possibility of contact between them and makes it easier to maintain order between successive production stages. From our experience, proper organization of component flow can significantly reduce the risk of damage without making the production process itself more complicated. What Should Be Done If Damage Is Detected Between Operations? Detecting damage between CNC machining stages does not always mean that the component must automatically be rejected. First, the location and nature of the damage should be assessed, along with its impact on the requirements specified in the technical documentation. This assessment should be carried out before the next operation begins so that work is not continued on a component that will ultimately be unable to meet the final requirements. Depending on the type of problem, rework, additional inspection, or withdrawal of the component from further production may be possible. You can read more about verifying component conformity in the article: “Quality control in CNC machining – how do we ensure precision at SIM Gdynia?”. Summary Protecting a component between successive operations has a direct impact on the final quality of production. Even correctly performed CNC machining will not guarantee that the component meets the requirements if previously finished surfaces are damaged during transport, storage, or subsequent technological operations. Proper surface protection, carefully planned transport, and good process organization help reduce this risk and preserve the quality of the component until the end of production. Are you planning to outsource CNC machining of demanding components? Contact us and send us your project documentation.
What Does CNC Machining of Eccentric Components Involve and Where Is It Used?
Eccentric components are used in mechanisms where one axis is intentionally offset relative to another. This type of solution is applied, among other things, where rotary motion needs to be converted into linear or oscillating motion, or where the position of a cooperating component needs to be adjusted. Producing such parts requires not only maintaining the correct dimensions, but also ensuring the precise position of the axes and surfaces in relation to one another. For this reason, CNC machining of eccentric components requires proper referencing, stable clamping, and the correct sequence of operations. What Are Eccentric Components and How Do They Differ from Axial Parts? In a typical axial component, the rotational surfaces share a common axis. In an eccentric component, at least one of them has an axis that is offset from the main axis of the part. The size of this offset is defined in the technical documentation and has a direct impact on how the component operates later. This type of geometry can be found, among other things, in eccentric shafts and journals, adjustment components, and parts of drive mechanisms. From a production perspective, it is important not only to achieve the required diameters, but also to maintain the specified axis offset and the correct relationship between the axes. These relationships are what distinguish machining eccentric components from standard axial parts. How Is CNC Machining of Eccentric Components Carried Out? The manufacturing method depends on the geometry, dimensions, material, and requirements specified in the documentation. The process may include turning, CNC milling, or a combination of several operations. Before production begins, the process engineer analyzes the position of individual surfaces, the referencing method, and the sequence in which they should be machined. The aim is to prepare the process so that each subsequent operation maintains the correct relationship to the previously machined features of the part. Part Setup and Determining the Machining Axis In the case of an eccentric surface, the axis of the machined section is located outside the main axis of the component. Therefore, the clamping method must take the required offset into account. In our work, we pay particular attention to establishing the correct reference surfaces during the first stages of CNC machining. A setup error can affect the position of subsequent surfaces, even if their individual dimensions are machined correctly. Turning and Milling Eccentric Surfaces Eccentric surfaces can be produced using different machining methods. For rotational components, offset-axis turning can be used, while CNC milling makes it possible to produce more complex geometries. The choice of CNC machining method also depends on the required tolerances, production quantity, tool access, and the ability to clamp the component securely. In more complex projects, it may be necessary to combine several machining operations. What Affects the Accuracy of CNC Machining of Eccentric Components? In eccentric components, not only the accuracy of individual dimensions matters, but also the position of the axes and surfaces relative to the defined references. The final result is influenced by the clamping method, component rigidity, operation sequence, and dimensional inspection after CNC machining. In serial production, it is equally important to maintain the same machining conditions for every component. Clamping, Rigidity and Process Stability The component must be clamped in a way that ensures a clearly defined position and sufficient rigidity during cutting. Insufficient stability can lead to vibration, poorer surface quality, and problems maintaining the required dimensions. From our experience, in the case of more demanding components, preparing the CNC program alone is not enough. An earlier analysis of the entire process and potential sources of error is equally important. Inspection of Axis Position and Dimensions Inspection should cover both the basic dimensions and the relative position of the machined surfaces. Depending on the technical documentation, this may include checking diameters, distances between axes, runout, and geometric tolerances. A component may have the correct diameter while still failing to meet the requirements for its position relative to the rest of the geometry. You can read more about component inspection in the article: “Quality control in CNC machining – how do we ensure precision at SIM Gdynia?”. The Most Common Challenges in CNC Machining of Eccentric Components One of the main challenges is maintaining the correct relationship between surfaces produced during different machining operations. Each new setup may introduce an additional deviation, which is why the machining sequence and referencing method are so important. The geometry of the component also matters. An offset center of gravity, limited rigidity of certain sections, or restricted tool access may require changes to the clamping method or cutting parameters. For larger production runs, an additional challenge is maintaining the same accuracy across all components. You can read more about preparing a stable production process in the article: “From documentation to stable production – the work of a technologist at SIM Gdynia”. Where Are Eccentric Components Used? Eccentric components are used where an axis offset is required to generate a specific motion or adjust the position of other parts of a mechanism. CNC machining makes it possible to produce such components both as individual parts and as part of repeatable serial production. Typical applications include: In each of these applications, the eccentric geometry performs a specific function, so the accuracy requirements should result from the actual operating conditions of the component. Summary CNC machining of eccentric components requires not only maintaining the correct dimensions, but above all ensuring the proper position of the axes and surfaces relative to one another. Proper referencing, stable clamping, the correct operation sequence, and final inspection of the component are all essential. A well-prepared process helps reduce the risk of errors and maintain the required repeatability both for individual components and for larger production batches. Do you need components with demanding geometry? Contact us. We will analyze your documentation and select the appropriate CNC machining method.
CNC Machining of Cast Components – How to Account for Surface Irregularities and Casting Variability?
Castings are widely used as semi-finished products for manufacturing components across many industries. They reduce the amount of material that must be removed and shorten machining time, but they also present manufacturing engineers with challenges that differ from those associated with rolled stock or bar material. With castings, the actual geometry of the workpiece may differ from the nominal CAD model. Surface irregularities, local distortions and variations between production batches mean that CNC machining requires careful process planning from the very beginning. How can you account for casting variability while maintaining the required quality of the finished component? Why Does CNC Machining of Cast Components Require a Different Approach? Unlike rolled or forged materials, every casting can differ slightly from the previous one. The shape and machining allowance distribution are not always identical. Even when castings are produced from the same documentation, small differences between individual parts may affect subsequent CNC machining operations. For the manufacturing engineer, this means evaluating not only the geometry of the finished component but also the actual condition of the casting itself. Decisions regarding datum selection, machining sequence and overall process preparation are made at this stage. When machining castings, process consistency is the key factor. A well-planned manufacturing strategy minimizes the influence of natural variations between castings and ensures repeatable production. For more than 45 years, we have been developing our expertise in manufacturing precision mechanical components, continuously investing in machining equipment, inspection capabilities and the development of our engineering team. This allows us to deliver demanding projects for customers across a wide range of industries. How Does Casting Variability Affect CNC Machining Preparation? Every machining process begins with evaluating the semi-finished workpiece. It is important not only to verify whether the casting matches the documentation but also whether sufficient machining allowance is available to produce all required surfaces according to specification. Already at this stage, it is possible to identify features that may affect the CNC machining process and determine the most appropriate manufacturing strategy. Machining Allowances and the Actual Position of Surfaces The nominal machining allowance specified in the documentation does not always correspond to the actual amount of material available on a particular casting. In some areas it may be larger or smaller, while certain surfaces may be shifted relative to the CAD model. If these deviations are not considered during process planning, unmachined areas may remain on the finished component or, conversely, too much material may be removed. For this reason, before CNC machining begins, it is worth verifying whether sufficient machining allowance is available in all critical areas of the component. This significantly reduces the risk of problems during subsequent machining operations. Distortion and Differences Between Individual Castings Minor distortions and dimensional differences between casting batches are a natural occurrence. Their extent depends on factors such as the manufacturing process, the material and the overall size of the casting. This does not mean that every casting requires an individually prepared machining program. Far more important is designing a process that accommodates acceptable casting variation while maintaining production repeatability. A properly developed manufacturing process should be robust enough to tolerate the typical deviations occurring between individual castings. As a result, production remains stable and finished components consistently meet documentation requirements. How Should Cast Components Be Properly Located and Clamped? The locating strategy directly affects the dimensional accuracy of the finished component. With castings, raw surfaces are often neither perfectly flat nor parallel, making the selection of suitable reference surfaces particularly important. Proper workpiece location minimizes the influence of casting irregularities on subsequent CNC machining operations. Selecting Reference Surfaces Reference surfaces should provide stable positioning while allowing all required features to be machined according to the technical documentation. This means selecting areas of the casting that exhibit the lowest variability and ensure the correct position of machined features. Already during process planning, it is worth analysing which surfaces are best suited as machining datums. Choosing the right reference points improves repeatability and reduces the risk of errors during subsequent setups. The Importance of the First Machining Operation The first machining operation often determines the success of the entire manufacturing process. It creates the reference surfaces that become precise technological datums during later setups. The quality of the initial setup directly influences all subsequent CNC machining operations. Properly machined reference surfaces make it much easier to maintain the required dimensional accuracy throughout the process. You can learn more about production planning in our article “From documentation to stable production – the work of a technologist at SIM Gdynia“. How Can the Impact of Casting Variability on Component Quality Be Reduced? Completely eliminating differences between castings is not always possible. However, the manufacturing process can be designed to accommodate these variations. In practice, this includes: In our daily work, we often encounter projects where the biggest challenge is not the CNC machining itself but preparing a process suited to a specific type of casting. Experience gained from a wide variety of projects allows us to identify potential issues long before production begins. Inspection of Cast Components Before and After CNC Machining Inspection starts before the cutting tool makes its first pass. Depending on the project, this may include verifying casting dimensions, available machining allowances and the position of the most critical surfaces. For more demanding components, this early inspection makes it possible to determine whether casting variability could prevent the part from being manufactured according to the technical documentation. Identifying such issues early helps avoid unnecessary production downtime. After CNC machining is completed, the finished component is inspected to verify compliance with the technical documentation. This confirms that, despite the natural variability of the casting, the finished part meets all project requirements. You can learn more about our inspection process in the article “Quality control in CNC machining – how do we ensure precision at SIM Gdynia?“. Summary Castings are an efficient way to prepare semi-finished products for manufacturing a wide range of components. However, their natural variability requires a carefully planned
CNC Machining Based on Customer Documentation – What Is Required to Prepare Production?
Production preparation in CNC machining begins long before the machine tool is started. The first step is to analyse the technical documentation provided by the customer. Based on this documentation, the feasibility of manufacturing the component is assessed, the machining technology is selected, the production process is planned, and the quotation is prepared. Complete and well-structured documentation reduces the need for additional clarifications, speeds up production planning and minimizes the risk of errors already at the implementation stage. So, what information is necessary to start manufacturing CNC components efficiently? Why Technical Documentation Is Essential in CNC Machining Every project begins with a review of the technical documentation. It is the basis for determining whether a component can be manufactured according to the specified requirements and which technological solutions will be the most appropriate. For more than 45 years, we have been delivering precision CNC machining projects for customers across a wide range of industries. From our experience, well-prepared technical documentation is one of the most important factors influencing efficient production planning and reducing the number of changes during later project stages. Documentation also affects the selection of raw material, the machining sequence, the fixturing method and the quality control plan. The more information the manufacturer receives at the beginning of the project, the easier it is to establish a stable and repeatable CNC machining process. What Information Is Required to Prepare CNC Machining? The more complete the information provided during the quotation stage, the faster the CNC machining process can be prepared and production can begin. A technical drawing alone is not enough. Information about the material, quality requirements and the intended application of the component is equally important. Providing these details early makes it possible to reduce unnecessary discussions and move more efficiently to the next stages of production. Technical Drawings and 3D Models in CNC Machining Technical documentation forms the foundation of every production process. In most cases, it includes manufacturing drawings in PDF format together with 3D models, such as STEP files, which significantly simplify process planning. The documentation should include: For more demanding projects, information about geometric tolerances and surfaces requiring special inspection is also essential. You can read more about this topic in our article “Dimensional and fit tolerances – how to optimise IT classes in CNC machining to avoid overpaying?“ Material, Batch Size and CNC Machining Requirements Besides geometric documentation, information about the material, production quantity and quality requirements is equally important. These factors influence CNC machining preparation, raw material selection and the planning of subsequent manufacturing operations. Before production begins, it is worth specifying: From our experience, clarifying these details already at the quotation stage significantly streamlines production planning and reduces the need for additional technical discussions. What Can Delay CNC Production Preparation? Not every documentation package allows the technological process to be prepared immediately. Some projects require additional clarification, which extends both the quotation stage and production planning. The most common issues include: In our daily work, we often find that the greatest challenge is not the CNC machining itself, but clarifying the technical requirements before production begins. The sooner these issues are resolved, the faster production preparation can move forward. How Documentation Analysis Affects the CNC Machining Process Analysing technical documentation is about much more than preparing a quotation. It provides the basis for planning the entire production process—from selecting the raw material and cutting tools, through fixturing methods, to machining operations and final inspection. In many cases, potential improvements and manufacturing risks can already be identified at this stage, helping to optimise the production process before machining even begins. The manufacturing process is prepared by a manufacturing engineer, whose role is to translate the customer’s documentation into a stable and repeatable production process. You can learn more about this role in our article “From documentation to stable production – the work of a technologist at SIM Gdynia“. Thanks to this preparation, production can begin efficiently while ensuring that finished components fully comply with the requirements defined in the technical documentation. Summary Complete technical documentation makes production preparation faster, shortens project analysis time and reduces the risk of misunderstandings during manufacturing. The earlier the key component requirements are defined, the easier it becomes to select the appropriate technology, choose the right tooling and establish a stable CNC machining process. In practice, documentation is not always complete from the start. Before production begins, it is therefore worth verifying whether it contains all the information required to prepare the manufacturing process. This helps avoid unnecessary questions, speeds up the quotation process and makes project execution more efficient. If you are planning to outsource CNC machining and would like to verify your project documentation, contact us. We will help you prepare a manufacturing process tailored to your component and production requirements.
SIM Gdynia at the AHK Poland Summer Evening 2026
We took part in the AHK Poland Summer Evening 2026, one of the largest Polish-German business gatherings organised by the German-Polish Chamber of Industry and Commerce (AHK Poland). The event brought together more than 400 representatives of member companies, business partners and the wider business community. Held at Forteca Kręgliccy in Warsaw, the meeting provided an opportunity for discussions, exchanging experiences and building relationships between companies operating in the Polish and German markets. Discussions and new opportunities for cooperation The programme included networking sessions, business meetings and numerous discussions on the development of economic cooperation between companies representing different industrial sectors. For SIM Gdynia, participating in events of this kind is an opportunity to meet new business partners, exchange experiences and follow market developments. Face-to-face meetings help us better understand the needs of companies and build relationships that may lead to joint projects and new opportunities for cooperation in the future. The importance of business relationships Modern industry relies not only on technology and manufacturing capabilities but also on strong business relationships. This is why we regularly participate in industry events, conferences and meetings that bring together members of the business community. We would like to thank the organisers for preparing the event and all participants for the valuable discussions and exchange of experiences.
Surface Roughness Under the Microscope – From Ra to Rz: How Cutting Parameters Define Final Quality in CNC Machining
In CNC machining, dimensional accuracy is only one of the factors that determine part quality. Even a component manufactured according to the technical drawing may fail to perform its intended function if the machined surface does not meet the project requirements. For this reason, technical documentation often specifies surface roughness requirements using parameters such as Ra and Rz. Surface roughness affects not only the appearance of a component but also its durability, sealing performance, and interaction with other parts. Why Surface Roughness Matters in CNC Machining Every machined surface contains microscopic irregularities created by the cutting action of the tool. Their size and characteristics depend on many factors related to the manufacturing process. Surface quality requirements should always be adapted to the function of the component. Not every surface requires the same level of finish, but in the case of mating surfaces, guide surfaces, and sealing surfaces, roughness can directly affect the performance of the finished product. Excessive surface roughness can accelerate component wear, increase friction, or make it difficult to achieve the required sealing performance. On the other hand, unnecessarily strict surface quality requirements often lead to higher production costs. Surface quality is particularly important wherever even minor deviations can affect component functionality. A good example is the medical industry, which we discuss in more detail in the article: “CNC Machining in the Medical Industry – Surface Quality Requirements” Ra and Rz – What Do They Tell Us About a CNC-Machined Surface? Ra and Rz are among the most commonly specified surface roughness parameters in technical drawings. Both describe surface condition, but each provides information about a different aspect of surface quality. In CNC machining, roughness parameters affect component interaction, sealing performance, and durability during operation. Understanding the differences between Ra and Rz is therefore important when defining quality requirements. Why the Ra Parameter Does Not Show the Whole Picture Ra represents the arithmetic average of surface profile deviations over the measured length. It is the most commonly used roughness parameter and appears in a large proportion of technical documentation. However, Ra provides only an average value. Two surfaces may have the same Ra value while differing significantly in the shape and depth of their irregularities. From the perspective of sealing performance, friction, or component interaction, these differences may be important. For this reason, when planning a CNC machining process, evaluating surface quality based on a single parameter does not always provide enough information to determine the actual requirements of the component. When Rz Becomes More Important Rz describes the height of surface irregularities, taking into account the differences between the highest peaks and deepest valleys of the profile. This makes it possible to evaluate not only the average surface condition but also larger irregularities that may affect component performance. This parameter is particularly useful when evaluating mating and sealing surfaces, as well as components exposed to operational wear. It can help identify local irregularities that may affect sealing performance or component durability. For this reason, in many industrial applications, Rz analysis provides valuable additional information alongside Ra measurements. What Determines Surface Roughness After CNC Machining? Achieving the required surface quality in CNC machining is not the result of a single technological decision. Even when working from identical technical documentation, the final result may vary depending on machining parameters, material properties, and tool condition. Surface roughness requirements should therefore be considered in the context of the entire production process rather than a single machining operation. Cutting Parameters and Tool Condition Machining parameters are among the most important factors affecting surface quality. Feed rate, cutting speed, and depth of cut directly influence the characteristics of the marks left by the cutting tool. In our work, we often encounter situations where a seemingly minor adjustment to machining parameters has a greater impact on the final surface quality than the choice of material itself. Tool condition is equally important. A worn cutting edge can reduce surface quality, increase surface irregularities, and produce unwanted machining marks. Workpiece Material and Process Rigidity Not every material behaves in the same way during machining. Aluminium, structural steel, stainless steel, and brass have different properties that affect the cutting process. For this reason, machining parameters should not be selected solely on the basis of component geometry. Material properties and the required surface quality after CNC machining are equally important. Parameters that work well for one material may not produce the same result when machining another component. The rigidity of the entire machining system also plays an important role. Vibrations generated during machining can leave marks on the surface that become visible during quality inspection. Where Are Surface Roughness Requirements Particularly Important? Not every surface of a component requires the same level of finish. Surface roughness requirements should therefore result from the function that a given feature performs in the finished product. We often work with components where surface quality requirements are just as important as the dimensional tolerances specified for CNC machining. Particular attention is paid to: Hydraulic components are a good example, as surface quality directly affects sealing performance and system durability. Surface Roughness Inspection After CNC Machining Achieving the required surface quality depends not only on the manufacturing process but also on effective inspection. Surface roughness is measured using specialised measuring instruments that make it possible to determine the required parameter values. This allows compliance with technical documentation to be confirmed before the component moves to subsequent production stages. We discuss our approach to quality control in more detail in the article: “Quality control in CNC machining – how do we ensure precision at SIM Gdynia?” Does Lower Surface Roughness Always Mean a Better Part? One of the most common mistakes is assuming that the lowest possible Ra value will always be the best solution. In our work, we often encounter situations where surface roughness requirements are stricter than the actual function of the component requires. Overly restrictive surface roughness requirements can lead to: For this reason, surface quality requirements should be defined according
Family Picnic for Children’s Day – Time Together for the SIM Gdynia Team in Chwaszczyno
On 14 June 2026, the Family Picnic for Children’s Day took place at Toyota Arena Stadium in Chwaszczyno. The event was organized with the idea of spending time together in a family-friendly atmosphere. The programme included many attractions for children and adults, such as animations, competitions, artistic performances, inflatable attractions, family sports activities and a food zone. It is an event that has attracted the local community for years and creates a space for shared celebration, conversations and good fun. We are pleased that this year we once again managed to gather enough participants to prepare a SIM Gdynia zone for our employees and their loved ones. It was a space for spending time together, talking and relaxing with prepared snacks and drinks. Time Together Outside Everyday Work Our zone was a place where we could meet outside the everyday work environment, spend time with our families and simply be together in a less formal atmosphere. It was also an opportunity to share a meal, talk and take a moment to rest during the event. Such initiatives are of great value to us because they help build relationships not only within the team, but also among families and loved ones, who are an important part of our employees’ lives. In the daily pace of work, there is not always space for such meetings, which is why we appreciate even more the opportunity to take part in local events together. Engagement in Local Initiatives For us, it is not only an opportunity for integration, but also a way to support initiatives taking place in our closest surroundings. We are happy to get involved in events that bring people together and create a positive atmosphere around spending time together. The weather was good, and the whole event took place in a friendly and family-oriented atmosphere. It was a good opportunity to spend time together and meet outside everyday professional duties. Thank you to all participants for the time spent together, and see you at the next events!
SIM Gdynia at the Polish-Swedish Defence Industry Forum
We took part in the Polish-Swedish Defence Industry Forum organised by the Ministry of Economic Development and Technology. The event brought together companies and institutions connected with the defence sector, creating an opportunity to discuss international cooperation, technological development and new investment opportunities. The forum took place at a time when cooperation between Poland and Sweden in the defence industry is becoming increasingly important. The topics discussed included opportunities to develop industrial partnerships, technology transfer, the participation of companies in international supply chains and joint research and development projects. Discussions on the future of the defence sector The event brought together representatives of public administration, technology companies and businesses operating in the defence sector. The forum provided an opportunity to exchange experiences and explore the prospects for cooperation between Polish and Swedish organisations. Particular attention was given to security, modern technologies and strengthening Europe’s industrial capabilities. Discussions also focused on the role of manufacturing companies in projects of strategic importance to the economy and defence sector. Cooperation opportunities for Polish companies The meeting brought together dozens of companies from Poland and Sweden. Each company had the opportunity to present its activities, capabilities and potential areas of cooperation. For SIM Gdynia, participating in events of this kind is an opportunity to follow market developments and build relationships with partners operating in sectors that require high quality and precision in the manufacturing of mechanical components. The growth of the defence industry and new technology projects create opportunities for cooperation between manufacturers, technology providers and production companies. SIM Gdynia in the defence sector For several years, we have been consistently developing our capabilities in the production of components for the defence sector. Participating in industry events allows us to better understand market needs, explore new directions in technological development and establish valuable business relationships. We would like to thank the organisers for the opportunity to participate in the event and everyone involved for the inspiring discussions about the future of the defence industry and international cooperation.