Copper is a versatile metal used in many manufacturing industries. From connectors to electric vehicle batteries, the use of copper components is unlimited. When it comes to copper fabrication, it is normal to wonder how effective CNC milling machines can cut copper pieces. With the right cutting parameters and proper heat management system, it is possible to mill copper with high accuracy and precision.
Read on to find out everything on copper CNC milling, how to cut copper with a milling machine, and the applications of CNC-milled copper parts.
What is a CNC Mill
A CNC mill is a machine that uses computer numerical control technology and a multi-point rotary cutter to shape a workpiece. To use a CNC milling machine, you place the workpiece on the worktable and attach the cutting tool to a spindle. The workpiece remains stationary while the tool engages and disengages to remove excess material.
There are different types of CNC mills you can use to machine materials. The most common are the 3-axis and 5-axis CNC milling machines. 3-axis CNC is the simplest multi-axis milling machine. This machine moves along three linear axes X, Y, and Z to cut simple features and straightforward designs. However, 5-axis CNC milling machines are more sophisticated. In addition to the linear axes, the cutting tool moves along additional rotational axes A and B. This makes it possible to produce more complex shapes and accurate components.
Can a CNC Mill Cut Copper
Yes, it is possible to cut copper workpieces to the desired shape and size. However, it can be challenging to work on pure copper because of its softness and gummy nature. Copper tends to stick to the cutting tool which can compromise the quality of the cut and lifespan of the tool itself. You have to take several precautions when cutting pure copper to get the best result.
Use sharp tools made from carbide or high-speed steel to machine copper workpieces. These materials can withstand copper’s unique characteristics and prevent the formation of burrs. You should also optimize the cutting parameters such as speed and feed rate to prevent excessive chip formation. Additionally, use proper cooling and lubrication systems to reduce heat generation and prevent copper from sticking to the cutting tool.
How to Cut Copper with a CNC Mill
The process of cutting copper with a CNC mill is similar to other metals. You begin with a block of copper then gradually shape it to get the finished product. Let’s look at a step-by-step guide on how to cut copper using a milling machine.
● Workpiece Preparation
The first step is to choose the particular copper metal you want to work with and prepare it. Clean the surface with appropriate agents to remove dirt, dust, and other contaminants. Remove all burrs and ensure the edges are smooth. Thereafter, dry the surface of the workpiece using a clean and soft cloth.
● Creating the CAD Model
The next step is to create a digital model of the final design. You do this using CAD software such as Fusion 360 or AutoCAD. When designing the CAD model for copper, avoid too complex features or thin-walled sections that can deform during machining.
● Converting to CNC-compatible Format
You then convert the 3D model of the part to be machined to a language the CNC milling machine understands in the form of G-codes and M-codes. G-codes give instructions on how and where the cutting tools should move. M-codes, on the other hand, deal with miscellaneous functions such as spindle off and on and coolant control.
● Milling Machine Set-up
The next step is to set up and configure the milling machine. It is at this stage you select the most appropriate cutting tool and calibrate the machine. You then choose a proper cooling system to ensure sufficient heat dissipation.
● Executing the Operation
Once everything is set, execute the operation and machine the part. When cutting copper material, make sure you attach a chip breaker to the cutting tool as long copper chips will lead to a poor finish.
● Inspection and Quality Control
When the operation stops, remove the part from the work holding fixture and inspect for defects and flaws. You can either use hand metrology tools or coordinate measuring machines. The choice depends on the complexity of the part and what you want to measure.
Pros and Cons of CNC Mill Cut Copper
The process of cutting copper workpieces using a CNC mill comes with unlimited benefits. Let’s look at some of the advantages of CNC mill-cut copper
● High Precision and Accuracy
A CNC milling machine cuts copper with a high level of precision and accuracy. The process is automated and devoid of human errors. It is possible to achieve tight tolerances even in the micrometer range. This feature is important when you have to further assemble the copper parts to make a whole.
● Versatile
Copper CNC milling is a versatile process. You can work with a wide range of copper grades including pure copper, electrolytic copper, and oxygen-free copper. All you have to do is optimize the cutting parameters. Furthermore, you can machine both small and large parts exactly to specifications.
● Complex Shape Capabilities
There is no limit to the shape the copper CNC milling process can create. It is a subtractive manufacturing process that crafts detailed designs and intricate features on a part. With it, you can produce complex undercuts and cavities that would have been difficult with conventional techniques.
● Fast Production Times
The speed of CNC milling of copper components is second to none. The machine is automated and can run continuously without human intervention. This makes copper CNC milling ideal for mass production of parts.
Copper CNC milling comes with the following limitations.
● High Tool Wear and Tear
Copper is a soft and malleable metal which is a serious shortcoming. When cutting copper pieces, you will find it sticking to the tool. This wears out the cutting tool in time. Hence, you may need specialized cutting tools which can be expensive.
● High Thermal Conductivity
The high thermal conductivity of copper metal can cause problems during CNC milling. The workpiece generates heat quickly which can damage the cutting tool. To mitigate this, make sure you use adequate cooling systems to prevent overheating.
Applications of CNC Milled Copper Parts
Copper CNC milling is versatile and suitable for use in many industrial applications. From radiators to gas welding nozzles, CNC-milled copper parts play significant roles. The following are some common ways you can use copper components.
● Electrical and Electronics
The use of CNC-milled copper parts in the electrical and electronics sector is nothing new. Copper conducts electricity readily which makes it ideal when manufacturing electrical structures such as heatsinks, bush bars, circuit boards, and connectors.
● Energy and Power Generation
CNC-milled copper parts also play a role in the renewable energy and power generation world. With this metal, you can create corrosive-resistant components that meet the industry’s tight tolerances. Examples of CNC copper parts used for power generation include wind turbines, solar panels, and transformers.
● Automotive Industry
You can also use CNC-machined copper parts when manufacturing automotive parts. Copper is important for the power management system of electric vehicles. Additionally, they are the go-to material when fabricating battery connectors, radiators, electric motors, and alternators.
● Medical Devices
Part manufacturers have been using CNC-milled copper parts in the medical industry for many years. The reason for this is not far-fetched. Copper is biocompatible and does not react with bodily fluids and tissues. Furthermore, it has antimicrobial properties which makes it useful when manufacturing surgical instruments, implants, and medical imaging equipment.
Conclusion
A CNC mill can cut different metals and copper is one of them. However, the softness of copper and the tendency to generate heat present unique challenges. With the right milling parameters and the use of specialized tooling, you can machine copper pieces with precision and efficiency. Before working on this metal, it is important to understand its mechanical properties to avoid mistakes and get the most out of copper CNC milling.
