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~ Can CNC Plasma Cutters Work With Aluminium? ~

Brick Digital • December 21, 2023

The demand for intricate designs using lightweight and versatile Aluminum prompts the question: Can CNC plasma cutters handle it?

In the ever-evolving landscape of metal fabrication and precision engineering, the synergy between cutting-edge technology and the intrinsic qualities of materials has reshaped the possibilities within industries such as aerospace, automotive, and beyond. As the spotlight turns toward Aluminium, a metal renowned for its light weight and versatility, there's a growing demand for intricate and complex designs using this material. No wonder why many seek answers to this crucial question: Can CNC plasma cutters effectively handle Aluminium?


If you are wondering the same, you have come to the right page! In this article, we will share the nuances of CNC plasma cutting, examining its compatibility with Aluminium, exploring the advantages and challenges of aluminium cutting, and envisioning the future of precision engineering. Let's dive right in!


Understanding CNC Plasma Cutting


CNC technology has become synonymous with precision and automation in the manufacturing world. In the realm of metal cutting, CNC plasma cutting stands out for its ability to slice through various materials with unparalleled accuracy. Utilising a combination of numerical control and a high-velocity jet of ionised gas, CNC plasma cutters are capable of creating intricate shapes and designs.


The process involves a computerised system interpreting design specifications and translating them into precise movements of the plasma torch. This level of automation not only enhances the accuracy of cuts but also allows for the creation of intricate patterns that would be challenging with traditional cutting methods.


Characteristics of Aluminium


Before delving into the compatibility of CNC plasma cutting with Aluminium, it's essential to understand the unique characteristics of this metal. Aluminium is known for its excellent strength-to-weight ratio, corrosion resistance, and thermal conductivity. However, these very characteristics present challenges when it comes to traditional cutting methods.


The lightweight nature of Aluminium can make it susceptible to warping or distortion from excessive heat during cutting. Additionally, its high thermal conductivity requires a cutting method that can efficiently manage heat. CNC plasma cutting, with its controlled and focused application of heat, emerges as a potential solution to these challenges.


Plasma Cutting vs Laser Cutting: Which One is Better for Aluminium?


When it comes to cutting Aluminium sheets, fabricators often debate between plasma cutting and laser cutting. These are two different methods used in metal fabrication, each with its own strengths and weaknesses. In this article, we'll focus on comparing plasma cutting and laser cutting specifically for Aluminium sheet fabrication.


Cutting Range


Plasma cutters can only cut materials that conduct electricity, limiting them to metals. On the other hand, laser cutters can work on various materials with high precision. In terms of cutting range and material thickness, plasma cutting outperforms laser cutting. Plasma cutting can handle Aluminium sheets and plates up to 38mm in thickness, whereas laser cutting is limited to 12.7mm.


Precision


The precision of both methods depends on the thickness of the Aluminium. For thin sheets, sheet metal laser cutting provides a more precise cut, creating narrow slots with high accuracy, often less than 0.01mm. In contrast, plasma cuts have a larger slot with precision ranging between 0.5-1mm. However, it's worth noting that laser cutting's precision decreases significantly as the material thickness increases, while plasma cutting maintains higher precision when working with thick Aluminium sheets.


Productivity


Productivity varies based on the thickness of the Aluminium or other metals being cut. Laser cutting is more productive for thinner metals due to its speed, but its productivity decreases significantly with thicker materials. Plasma cutting, on the other hand, maintains better productivity with an increase in thickness.


Operation Cost


Beyond the initial investment, laser cutting machines also incur higher operational costs. On average, the operating cost for laser cutters is more than that of plasma cutters. This cost includes expenses for power, gases, maintenance, and replacing worn-out parts.


Equipment Cost


Investing in a laser cutter is a more expensive endeavour compared to purchasing a plasma cutter. The capital cost for laser cutters varies a lot, depending on the features you need, while you can acquire a plasma cutter for a much cheaper price.


In conclusion, the choice between plasma cutting and laser cutting for Aluminium fabrication depends on factors such as precision requirements, cutting range, equipment and operation costs, and the thickness of the material. Understanding these aspects will help you make an informed decision based on your specific needs and budget constraints.


Compatibility of CNC Plasma Cutters with Aluminium


CNC plasma cutting technology has evolved to handle a diverse range of materials, including Aluminium. The compatibility of CNC plasma cutting with Aluminium hinges on several factors. The type of CNC plasma cutter used plays a crucial role, as different machines come with varying power levels and capabilities.


When it comes to Aluminium cutting, the key is to fine-tune parameters such as cutting speed, gas flow, and torch height to accommodate the metal's unique properties. CNC plasma cutters equipped with advanced systems can effectively navigate through varying thicknesses of Aluminium, ensuring precision and consistency in the cutting process.


Advantages of CNC Plasma Cutting for Aluminium


CNC plasma cutting offers several advantages when it comes to working with Aluminium:


Precision and Accuracy: The CNC system's ability to interpret complex designs results in precise and accurate cuts, maintaining tight tolerances even on intricate patterns.


Versatility: Aluminium often requires cutting into complex shapes, and CNC plasma cutting excels in this regard. Its versatility allows for the creation of custom designs with ease.


Cost-Effectiveness: CNC plasma cutting proves to be a cost-effective solution for Aluminium cutting, especially when compared to laser cutting or water jet cutting methods. It strikes a balance between efficiency and affordability.


Challenges and Considerations


While CNC plasma cutting offers numerous benefits for Aluminium, it's essential to address potential challenges:


Thermal Considerations: Aluminium's high thermal conductivity can lead to heat-affected zones and potential distortion. Proper parameter settings and the use of advanced CNC systems can help mitigate these issues.


Edge Quality: Achieving a smooth edge finish is crucial in many applications. CNC plasma cutting may require additional post-processing steps to refine the cut edges for specific requirements.


Maintenance: Regular maintenance of CNC plasma cutters is essential to ensure optimal performance. This includes checking and replacing consumables, inspecting the torch, and monitoring the overall system for wear and tear.


Plasma Cutting Aluminium: A Quick Guide


Plasma cutting Aluminium is similar to cutting steel, but differences in gas, nozzle, and settings are crucial. Here's a simplified breakdown:


1. Gas Selection


Using regular air can result in rough cuts due to oxidation. Optimal gas mixtures vary:

  • For Aluminium over half an inch thick: Primary - argon-helium, Secondary - nitrogen.
  • For Aluminium under half an inch thick: Primary - nitrogen, Secondary - compressed air.


2. Nozzle Importance:


  • Nozzles made from copper alloy work best, conducting heat and electricity effectively.
  • Nozzle size affects cut angle, power, and size. Choose smaller orifices for larger arcs and higher voltages.
  • Check the temperature limit on the nozzle to prevent melting or reduced lifespan.


3. Machine Settings:


  • Consult your machine manual for accurate settings, including amperage and torch speed for Aluminium cutting.
  • Cutting speed is crucial; too slow wastes power, while too fast may lead to unsuccessful cuts.
  • Generally, cutting speeds range from 1695 mm/m to 4750mm/m, depending on arc voltage and Aluminium thickness.


Plasma cutting is an effective method for fabricating Aluminium parts, but success requires technical knowledge, skill, and the right equipment.


Reducing Risks in Aluminium Plasma Cutting


Use a Tank with Water Level Control

Lowering the water level helps release hydrogen molecules, reducing the risk of explosions.


Wear Protective Gear

Utilise a welding helmet, goggles, gloves, boots, jackets, earmuffs, and chaps to protect against sparks and radiation during plasma cutting.


Protect Eyes from UV Radiation

Wear goggles to prevent cornea burns from ultraviolet radiation generated during cutting (arc eye).


Install an Aerator

Setup with tubes releases air bubbles under the Aluminium, pushing hydrogen away and decreasing the risk of explosions.


Use a Bubble Muffler

Device shields plasma, using compressed air to eliminate hydrogen and direct Aluminium pieces away from the arc. Reduces UV radiation, noise, and fumes.


Install a Filtration System

Consists of a centrifuge and a high-volume pump to separate hydrogen early, preventing bubble formation. Also filters out contaminants from the water.


Avoid Unsuitable Aluminium Alloys

  • Anodized Aluminium: Vulnerable to high temperatures, damaging the metal surface during plasma cutting.
  • Aluminium Floor Plate: Raised sections interfere with the plasma cutter's control and result in poor cut quality.
  • Aluminium-Lithium Alloys: High volatility around water; cutting in water can lead to explosions or flames.


Immediate Removal of Aluminium Pieces in Water

If Aluminium pieces fall into the water during cutting, remove them promptly to prevent potential hazards.


By following these safety measures and precautions, the risks associated with hydrogen explosions and other hazards during Aluminium plasma cutting can be significantly minimised. Always prioritise safety and choose appropriate materials to ensure a secure and efficient cutting process.


Tips for Optimising CNC Plasma Cutting of Aluminium


To maximise the benefits of CNC plasma cutting when working with Aluminium, consider the following tips:


Setting the Right Parameters: Fine-tuning the cutting parameters is crucial. Adjust factors such as cutting speed, amperage, and gas flow to accommodate the specific characteristics of Aluminium and the thickness of the material.


Choosing the Appropriate Apparatus: Selecting the right apparatus, including nozzles and electrodes, is essential for achieving clean cuts. Specialised apparatus designed for Aluminium cutting can enhance performance and extend the life of the cutting components.


Regular Maintenance and Troubleshooting: Consistent maintenance is key to the longevity and efficiency of CNC plasma cutters. Regularly inspect consumables, check for wear, and perform routine maintenance to address any issues promptly.


Future Trends and Innovations


The world of CNC plasma cutting is ever-evolving, with ongoing research and development aiming to enhance the capabilities of these systems. When it comes to cutting Aluminium, future trends and innovations may include:


Advanced CNC Systems: Continuous advancements in CNC technology will likely result in more sophisticated systems with improved automation, allowing for even greater precision in Aluminium cutting.


Enhanced Cooling Systems: Innovations in cooling mechanisms may address the thermal challenges posed by Aluminium, ensuring optimal cutting conditions without compromising material integrity.


Integration with Advanced CAD/CAM Software: The integration of CNC plasma cutting systems with advanced CAD/CAM software has the potential to optimise the design-to-cutting process, further enhancing efficiency and accuracy.


Final Thoughts


The compatibility of CNC plasma cutters with Aluminium is not only feasible but also offers numerous advantages. The precision, versatility, and cost-effectiveness of CNC plasma cutting make it a compelling choice for various industries requiring Aluminium components with intricate designs. As CNC plasma cutting continues to evolve, we can expect even more efficient and effective solutions for Aluminium cutting in the future.


If you're looking to start on projects that demand the utmost precision and expertise in CNC machining and plasma cutting, look no further than Rotec. With a proven track record in handling complex CNC machining projects, our precision engineering team is ready to bring your visions to life. To explore the possibilities, contact us today!

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This will have an impact on the time and cost of the CNC machining services. Tips for reducing CNC machining costs There are a few ways in which you can reduce the cost of CNC machining, each dependent on what materials the project is using and the required end result, amongst other things. Here are a few tips to cut costs but not to cut quality. Optimise choice of materials Selecting the most appropriate material for your desired part is the crucial aspect of cutting costs. Raw materials will differentiate in cost, but also choosing the wrong material for the machines in use will cause potential problems in overspends and the time it takes to machine the part. You must find that balance between a low cost raw material that is optimal with how you wish to process it in line with the specific design requirements. Volume of production CNC machines have the ability to manufacture in both small and large quantities. Once up and running there is minimal supervision required, making it a cost-effective choice for large production runs. If only a prototype or a small batch of parts is required however, it might incur a high cost due to the initial set-up time. Minimise machine set-up If it is at all possible, cut down the number of machine set-ups, as this will always add to the costs. Larger quantities of parts will affect the unit price, helping to minimise overhead costs, as it is spread over many parts. Design parts that can be machined in just a few machine set-ups can help you to reduce costs, so consider separating a part into multiple geometries, to be assembled later. Limit tight tolerances When there is a part that includes a tight tolerance design, the cost will rise because it adds to the machining time and will require a closer, manual inspection. Tight tolerances often lead to a greater level of excess waste too, and slower machine times to maintain consistent accuracy of the part. Use standard holes Using standardised hole sizes throughout a design will help to reduce costs as it will eliminate the need for a specialist tool. Standard drill hole sizes lead to less intervention during the machining process and maintain a consistent speed of production and accuracy. Reduce designs with thin walls By increasing the thickness of thin walls, you’ll experience a reduction in machining time, and therefore a reduction in costs. Thick, solid sections offer stability and are less expensive to create. This is because the thinner the wall, the more likely it is to be prone to vibrations and to distort. Leave things blank Leaving out any engraving or detail on the finished part, such as text or logos, will help to reduce costs significantly. If you do require these extras, the costs will increase due to the need for extra machinery and processes to trace numbers, letters, and symbols, and the set-up time associated with this. What is the future of CNC machining? 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Cost effective CNC machining materials

By Jake Hughes • June 24, 2024
CNC machining is such an important part of manufacturing, with industries as varied as the medical industry, aerospace , and electronics all utilising the performance, accuracy, and speed of CNC machining for a variety of parts, components, and applications. Cutting costs without negatively impacting the end product is something that is always discussed, and CNC machining is no different. One way in which the costs associated with CNC machining can be lowered is through the careful choice of materials being used within each project.  What factors should you consider? There are a range of factors to consider when choosing the correct metal for your CNC machining needs. Even if you choose a metal that has a higher raw material price, if it is used correctly, with the right type of machining and gives you the desired end result, this will also mean it is the most cost-effective and desirable option for your project. Factors include: Availability of materials The cost of metals fluctuates depending on their availability in the market. Aluminium for example, often comes at a competitive price and is therefore a cost-effective choice, Machinability The higher the machinability of the machining material, the better the impact on the tools, with reduced tool wear and shorter machining times. This helps to lower labour and material costs. Set-up and tooling The hardness of a material, along with other characteristics, have an impact on tool wear and the requirements for specialised tooling. Always look for that balance where there are minimal set-up costs to help lower your budget. Minimise waste This is a crucial part of planning for CNC machining projects. Some materials, like certain alloys and plastics, have efficient use of raw materials, lowering the environmental and cost impact. Post-machining treatments How much surface finishing and coating will be required? This will have an impact on the overall cost of the project, with materials that require minimal post-processing leads to additional cost savings. Complexity of parts The more complex the parts required, the longer the machining time and therefore the higher the potential costs. Volume requirements What is the quantity of parts and components required? This will have an impact on costs, as the higher the volume requirements, the longer the production run. Industry standards In some cases, you’ll be required to produce components and parts to industry standards and regulations, as well as established machining parameters. Understanding this will help to create a streamlined manufacturing process. Consider the environment A suitable CNC metal for different environments is important, as you need to ensure that the CNC part can withstand the necessary pressure and temperature extremes. Weight of the part Considering the weight of the part will ease the manufacturing process, as heavier parts will drive up the material costs and require more expensive CNC machines and longer production times. Heat resistance Effective heat resistance is crucial for materials to withstand extreme temperatures without becoming damaged or disfigured during the process. Consistency is key within CNC machining. What are the most cost-effective metals for CNC machining? Some of the most cost-effective metals that are used for CNC machining include: Aluminium This is a metal that is available in a range of different alloys and is one of the most cost-effective metals that can be used for CNC machining. It is highly machinable (varying for different alloys slightly) and has a low raw material cost when compared with other metals. Aluminium has a high strength-to-weight ratio and has great resistance to both corrosion and temperature, making it useful within a range of industries, such as automotive, healthcare, aerospace and consumer goods, to name just a few. Stainless steel A popular, versatile CNC metal used within a variety of CNC machining applications. It is not as machinable as aluminium but does have good machinability to low raw material cost ratio. It is high in strength, resistant to chemicals and has good levels of hardness. Stainless steel is used commonly in the aerospace, automotive, marine, healthcare and food industries. Brass A cost-effective metal alloy that is made from a combination of zinc and copper. It has a higher machinability factor than stainless steel, but it has a higher cost of raw material. When comparing brass with other metals however, it does have a high level of scrap return, reducing the overall raw material cost. Brass is soft and easily machinable, which has a low impact on the machining tools, with a medium hardness and high tensile strength. Brass is used within the manufacture of consumer goods, architecture, electrical goods, and within the healthcare and automotive sectors. Copper A very high machinability rate in a similar way to brass, making it one of the most cost-effective of all CNC machining metals. The price of raw material can often be higher though, making it less cost-effective in other ways. It is commonly used in applications where there is a need for good thermal and electrical conductivity, and you’ll find copper used in industries such as electronics and healthcare due to good corrosion resistance levels. Titanium This has a higher raw material cost than the other metals in this list and can be challenging to work with due to the low thermal conductivity and high strength. There are a few unique properties though that make it a choice for some companies and for certain industries and applications. This is due to the excellent strength-to-weight ratio, and resistance to temperature, corrosion, and chemicals, making it useful within the medical and aerospace sectors specifically. There are different suitable metals for different CNC machines, different processes, and the many different desires and requirements for specific components and parts. Each is distinguished by different mechanical properties, such as strength, flexibility, resistance to corrosion, and other factors. Some materials, as you have seen above, are easier to machine than others, or are more suitable for specific components and parts for a variety of reasons. Understanding what materials work best for your specific CNC machining needs goes a long way to helping you manage your business, your project, and gaining a tighter control over the costs of CNC machining.

What is robotic cnc machining?

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The technology for automation and CNC robotics has grown considerably in recent years. The technological advancement of robotics and how it can be effectively incorporated into manufacturing techniques and processes make it one of the more prominent CNC machining processes . The implementation of robotics within CNC provides a range of benefits to the manufacturing industry. CNC robotics is the combination of both CNC and cutting-edge robotics to increase accuracy and efficiency within manufacturing. What is CNC machining? The basics of CNC machining are important to understand before heading into robotics further. A CNC turning machine can convert three-dimensional CAD designs into fully finished machine parts and components. CNC machining offers great advantages over manual machines, due to tighter tolerances, longer production runs, and increased speed of production processes. How do you define robotic CNC machining? CNC robotics is the combination of CNC (Computer Numerical Control) machines and cutting-edge robotics. CNC machines operate based on pre-programmed software and directions that control the movement of the machine. CNC robotics on the other hand, is any robotic process that is used within the CNC machining process that assists it. This is specialised, advanced robotic equipment that is designed for machining purposes only and does not require any input from the operator of the process. CNC robotics increases the advantages of automation within CNC machining and manufacturing, helping in the delivery of high-quality parts and components that are mass produced for a variety of purposes and industries. CNC robotics can be used to perform complex tasks with high levels of competency and consistency, making them an accurate assistance within mass production of parts in CNC machining processes. What are the common robotics used within CNC machining? 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Gantry (Cartesian) robots Linear industrial robots with three axes that are popular due to their highly flexible configuration options. The robot can be adjusted easily to change precision, speed, size, and stroke length. They are suitable for working with assembly, loading and unloading, material handling, as well as for laser and waterjet cutting tasks. What are the advantages of robotic CNC machining? CNC robotics are helpful in producing high-quality machine parts and components, but they are also able to manufacture robots too. The advantages of robotic CNC machining include: High speeds CNC machining with robotics significantly shortens production time, with custom robot parts created in rapid timeframes. Increased precision Robotic loaders are programmed for increased precision positioning, which helps to improve the efficiency of the entire CNC machining process. Smoother finishes CNC machines create components with smooth surfaces, with the functionality enhanced by the application of additional surface-finishing operations. Accuracy of geometry The dimensional accuracy of CNC machining ensures tight tolerances of up to 0.00002 in, helping to accelerate iterations of robot designs. Material compatibility Components for robots need to use materials that have excellent strength-to-weight ratios to ensure the safe and effective lifting and movement of heavy goods. What are the differences between CNC machines and CNC robotics? In terms of accuracy, CNC robotics continue to improve, with industrial robots reaching precision of between 0.1 and 0.2mm, whereas the highest quality of CNC machines can reach precision of between 0.02 and 0.05mm. The versatility of robots gives it an advantage, with robots able to move from one task to another with little downtime and no impact on efficiency. Robots have a lower rigidity than CNC machines, making them less accurate though robots can easily handle softer materials like plastic and wood with accuracy. As far as affordability is concerned, CNC machines can be expensive, but so too can robots with a large workspace required. Is the time coming where CNC robotics replaces CNC machines? Although there are advantages to robotic CNC machining, the technology does not quite yet match CNC machines in terms of the speed and precision that modern CNC machines can demonstrate. Robotic CNC machining does offer great versatility and adaptability for various tasks, but with specialist CNC machining for specific components and parts, these are a much better choice for large and long production runs where there is a need for consistency of single parts and components. What is the future of robotic CNC machining? With the development of robotics and the technology within CNC machining developing at a fast rate, there is a real view that CNC robotics will continue to revolutionise the manufacturing sector over the coming years and decades. CNC machinery and robots that are powered by AI could help to improve production processes, with customisation offering even greater possibilities for a wide range of applications. Robotics will help in 3D printing and additive manufacturing to create complex geometries and components, boosting industrial production and speed of production runs without diminishing the safety levels of operators on site. As the technology of CNC robotics improves, there will be a better chance for smaller companies and projects to take on board CNC machining processes, although it will still be the best choice to work with seasoned veterans in the field of CNC machining who have been at the vanguard of the industry for years and understand how to work within a whole host of industries and project parameters.

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What is feed rate in CNC machining?

By Jake Hughes • May 28, 2024
CNC machining is a process widely used within manufacturing where a metal piece is cut away from until the desired shape is achieved. This is called subtractive manufacturing, where a block of material is sheared and shaped, rather than added to in order to create the finished piece. For a CNC machining production run to be successful, the operator must understand the feed rate and cutting speed of the CNC machine, whilst also knowing the shearing capability and material being worked with. Although the process is driven by a computer and automated once in motion, this is a crucial part to the planning and set-up. What is feed rate? The feed rate of a CNC machine is the distance the cutting tool travels when looking at one spindle revolution. This is taken alongside the velocity at which the cutter is advanced against the workpiece. To think of it in a simple way, the feed rate is how fast the machine moves the router through the material during the cutting process. Feed rate is measured in units per minute. Why is feed rate important? The feed rate has a big impact on the effectiveness of the project, and will vary depending on the cutter being used, the material being shaped, and other factors. Feed rate will have a direct impact on the safety of the machine and project, the productivity of the project, the part quality and the finish of the surface. Over time, the feed rate will also have an impact on the wear of the CNC machine and its components. If you consider that the cutter is engaged at a high speed with the material and must go quickly from cutting at speed along a linear path, before stopping dead with precision to turn a corner and change direction before picking up speed again. This increases torque loads on the machine, and it is only natural that this would add to wear and tear factors on the CNC machine and components over time. Factors to consider with feed rate There are a few different factors that need to be considered when looking at the feed rate of a CNC machine. This includes: The type of tool – The type of tool that is being used to cut the material must be suitable to cut said material. What surface finish is required? – The roughness of the surface will increase as the feed rate increases. This means that to get a smooth finish on the material being worked on, the feed rate must be slowed down. TPI – TPI (or thread per inch) is an important metric, one that is proportional to the feed rate. As the thread pitch of the screws being used increases in range, the feed rate increases. The width of the cut – The chip may thin when the cut width is less than half diameter. To minimise the risk of this occurrence the feed rate must increase. What is the cutting speed? Cutting speed is something that shouldn’t be confused with the feed rate. They do work simultaneously, but they are not referring to the same thing. Cutting speed is the speed at which the tool cuts the workpiece, whereas the feed rate is the distance travelled by the tool in one revolution of the workpiece. Cutting speed is also referred to as the surface speed, as the relative velocity between the surface of the workpiece and the cutting tool. There is an optimum cutting speed that matches the conditions between specific machining conditions and specific materials. Factors to consider with cutting speed The optimum cutting speed must be found, as this improves the entire efficiency of the CNC machining process. This can be achieved through a few important factors, such as: The material being cut – The choice of cutting tool will depend on the material being used. For instance, a CNC lathe is compatible with different materials such as wood, glass, metals, and others, with different levels of thickness and hardness. A material that is too soft will lead to a cutting tool cutting with high speed and accuracy, with a lower cutting speed required for harder materials. The material of the cutting tool – Similarly, there are different types of cutting tools that can be used on a CNC machine. This can be made from hard or soft materials, with the optimum found by thinking of the strength of these materials and the speed required relating to the specific material of the workpiece. High-strength material for the cutting tool is useful for high-speed cutting, with a softer material used for low-speed cutting. The life cycle of the tool – The lifecycle of the tool is important, as this is the period in which the cutting tool works at its optimum level. Once this has passed, the accuracy and cutting speed will begin to diminish. What is feed rate optimisation? Feed rate optimisation is important, as it is a way to maximise the efficiency of the entire project and operation. It can help to preserve the CNC machine for a longer period of time, at an optimal level of performance. It allows you to set the distance before the corner to start feed rate reduction and to smooth the process of the cutting tool slowing down before turning a corner and getting back up to speed. Too low a feed rate can produce vibration, chatter and work hardening, along with poor surface finish and cutter failure. Too high a feed rate can cause chatter, vibration and unsafe conditions. Optimisation leads to safer and more effective conditions. Is there any other important terminology to understand? Here are a few more pieces of terminology to be aware of. Slew rate – This is also referred to as rapid speed. It is the speed at which the machine moves between cuts. The slew rate is commonly set as high as it can be, to help reduce downtime between cycles and to improve efficiency. Plunge rate – This is the speed the router is plunged (or driven down) into the material at the point where the cut is first beginning. The ideal plunge rate will be different depending on the bit being used and the material that is being cut, but you should never plunge too quickly, as this is more likely to cause damage to the cutter tip. Spindle RPM – The spindle speed (or RPM) is the rate at which the spindle revolves during the cutting process. It should always be set to an appropriate value that relates to the tool being used and the material being worked on. If you cut at a feed rate that is too low or a spindle RPM that is too high, the router can be at risk of overheating, which can lead to the workpiece melting or burning. There are more factors than just the feed rate and cutting speed that will have an impact on the efficiency of the CNC machining process and your specific projects. By working with experts in the field, these are not worries that you need to consider, as you’ll have the guidance and set-up to ensure optimal performance from your CNC machine.
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