CNC Aluminum Parts

CNC machining aluminum parts involves a series of steps from design to finishing. The following is a detailed description of how to CNC machine an aluminum part.

1. Design the part
-CAD Modelling: Start by creating a detailed 3D model of the part using CAD (Computer Aided Design) software. The model should include all critical dimensions and tolerances.

2. Preparing the CNC machine
-Material Selection: Select the appropriate aluminum alloy for the required properties and application of the part.
– Tool Selection: Select suitable aluminum alloy tools such as carbide or diamond coated tools to provide better durability and accuracy.
– Machine setup: Secure the aluminum workpiece to the CNC machine using a jig or vise to ensure stability during machining.

3. CNC Machine Programming

– CAM SOFTWARE: Use CAM (Computer Aided Manufacturing) software to convert a CAD model into a g-code programme which provides instructions for the movement of the machine.
– Toolpath: Defining the toolpath controls where and how the tool interacts with the aluminum. This includes setting the cutting speed, feed and depth of cut.

4. Machining Parts

– Cutting: Starts the CNC machine and monitors the cutting process. Aluminum is usually machined at high speeds with a suitable lubricant or coolant to prevent sticking and overheating.
– MILLING: Perform any drilling or milling operations as required by the part design.

5. Quality Control

– CHECKING: After machining, check the dimensional accuracy of the part using tools such as calipers, micrometers, or a coordinate measuring machine (CMM).
– Deburring: Remove any sharp edges or burrs formed during machining to ensure that the finish of the part meets specifications.

6. Finishing Process

– Surface Treatment: Apply surface treatment such as anodizing, painting, or powder coating to improve corrosion resistance, surface hardness, and aesthetics.
– Polishing: If a high gloss is required, polish the part to achieve the desired luster.

7. Assembly and Testing

– ASSEMBLY: If the part is part of a larger assembly, connect it to other parts as specified.
– Test: Perform functional tests to ensure that the part meets all operational requirements.

By following these steps, you can effectively and efficiently machine high-quality aluminum parts using CNC technology.

Aluminum is an excellent material choice for CNC machining due to several key advantages:

High machinability

– Aluminum is softer and more fragile, making it easier to cut and machine than other metals.
– Aluminum’s softness reduces tool wear and extends tool life, resulting in lower tool costs.
– Aluminum’s dimensional stability allows for the cutting of large amounts of material while maintaining tight tolerances.

Lightweight and Strong

– Aluminum has an excellent strength-to-weight ratio, providing good mechanical properties at a fraction of the weight of steel.
– This makes aluminum ideal for applications such as the aerospace and automotive industries that require lightweight, durable parts.

Corrosion Resistance

– Aluminum naturally forms an oxide layer that gives it good corrosion resistance in many environments.
– The corrosion resistance of aluminum can be further enhanced by anodizing it for more demanding applications.

Cost-effective

– Aluminum is typically less expensive than other metals such as steel or titanium.
– Due to its high machinability, aluminum takes less time and costs less to machine than harder metals.
– Aluminum parts are often faster and more economical to produce than other materials.

Versatility

– Aluminum alloys offer a wide range of mechanical properties for different applications by alloying with elements such as copper, silicon and magnesium.
– Common alloys such as 6061, 7075 and 2024 provide a good balance of strength, corrosion resistance and machinability for CNC machining.

In summary, aluminum’s excellent machinability, strength-to-weight ratio, corrosion resistance, cost-effectiveness, and versatility in a wide range of alloys make it an ideal material for the efficient and economical production of high-quality parts in a variety of industries.

The best way to cut aluminum depends on the thickness, quantity, and desired finish quality. Here are some recommended methods:

For thin sheet and bar stock (up to 1/4″ thick)

Use a miter saw or circular saw with a fine-tooth carbide blade designed for non-ferrous metals. Hold the workpiece securely and apply a lubricant like WD-40 to the saw blade to ensure a clean cut. For thin aluminum sheets, tin snips will also provide a clean cut.

For thicker aluminum sheets (over 1/4″ thick)

Band saws with bi-metal blades are ideally suited for this type of work and produce less scrap than circular saws. Modern band saws can cut aluminum sheets at optimum speeds with a clean cut. It is also good to use dry or cold cutting saws equipped with carbide blades, which run at slower speeds, prevent overheating and provide very clean cuts.

For high volume production or fine machining

CNC mills and lathes are ideal for high precision machining of aluminum parts and assemblies. Plasma cutters are capable of cutting long straight cuts in thick aluminum sheets by melting the metal with a jet of ionising gas.

Other options for small production runs

For cutting tubes or bars, a hacksaw can be used; for cutting pipes, a router can be used; and as a last resort, an angle grinder with a cut-off wheel can also come in handy. Whichever tool is used, holding the workpiece securely and using the right blade or disc designed for aluminum is essential for a clean cut.

6061 aluminium alloy

• One of the most versatile alloys for machining.
• Excellent machinability, allowing complex geometries to be machined to tight tolerances.
• Good corrosion resistance and weldability.
• Ideal for structural components, aircraft parts and electronics.

2024 aluminium alloy

• High strength-to-weight ratio and good fatigue resistance.
• Machinability is fair to good and produces uniform chips.
• Commonly used in the aerospace and transport industries where high strength is required.
• Prone to chipping during heavy cutting and therefore requires optimised toolpaths.

7050 Aluminum Alloy

• High toughness and mechanical strength, even at sub-zero temperatures.
• Machinability is better than 7075 alloy with less burr formation.
• Commonly used for aerospace components and thick plates.

7075 aluminium alloy

• Very high strength and hardness.
• It has an excellent surface finish and is suitable for precision machining.
• Typically used in applications requiring high strength and wear resistance, such as aerospace and military equipment.

Alloys 6061 and 2024 are the most commonly recommended alloys for machining due to their excellent machinability, desirable strength and corrosion resistance. Alloy 7050 is noted for its excellent machinability and less burr formation than 7075, although 7075 has a better surface finish.

Other factors such as cost, heat treatability and specific application requirements should also be considered when selecting the best machined aluminum alloy. For example, 6061 alloy is often used for a variety of general applications due to its good all-round properties and relatively low cost. Alloys 2024 and 7075 are more suitable for high strength and performance requirements. Consider all these factors to select the best aluminum alloy for your specific needs.

For high-quality custom aluminum CNC milled parts, you can confidently turn to RALLY. We specializes in CNC aluminum machining services, and provides tailor-made solutions based on your specific design requirements. We are equipped with advanced machinery and have extensive experience in handling a variety of aluminum alloys, ensuring precision and efficiency in every project.

Why choose RALLY for your aluminum CNC milling needs?

– Customisation: From simple parts to complex assemblies, RALLY specialises in producing parts that meet our customers’ exact specifications.
– Quality and Accuracy: With state-of-the-art CNC machines and skilled technicians, RALLY consistently delivers high precision, high finish parts.
– Wide range of aluminum alloys: Whether you need the high strength of 7075 or the superior corrosion resistance of 5051, RALLY offers a wide range of aluminum alloys.
– Competitive Pricing: Thanks to efficient processes and professional management, RALLY offers competitive pricing without compromising quality.
– Fast turnaround: RALLY recognises the importance of timely delivery and is committed to meeting tight deadlines while ensuring top quality.

To learn more about our services or to place an order for custom aluminum CNC milled parts, whether your project is big or small, RALLY is ready to meet your CNC machining needs with professionalism and precision.