Key Technical Points for Producing High-Quality Brass Turned Parts
Widely valued for their durability, versatility, and aesthetic appeal, brass turned parts are essential components and key components across many industries. These parts are crafted from a copper-zinc alloy using precision CNC machining.
This alloy is not only strong and durable, but also inherently corrosion-resistant, making it suitable for a wide range of applications. Furthermore, brass’ inherently bright surface imparts a unique visual quality unmatched by other materials.
Coupled with brass’s ease of machining into complex shapes and precise dimensions, brass turned parts find widespread use across a wide range of industries. From automotive parts to building components, from electronic equipment to plumbing systems, the applications of these precision parts are vast and diverse.
1.Brass Material Properties
Brass is a specific term that refers to various copper-zinc alloys with properties such as electrical and thermal conductivity, strength, hardness, wear resistance, ductility, and corrosion resistance.
The key properties of brass and their impact on processing are as follows:
Corrosion Resistance: Brass inherently has strong corrosion resistance, especially in saltwater environments. The addition of tin further enhances its corrosion resistance.
Machinability: Brass offers excellent machinability and is easily cut, turned, and formed, enabling the manufacture of complex shapes.
Ductility and Forgeability: Brass can be easily stretched, bent, and formed without breaking, making it suitable for stamping, drawing, and forging.
Electrical Conductivity: Brass has good thermal and electrical conductivity, making it suitable for machining parts requiring electrical or thermal conductivity.
Aesthetics: Brass has a warm golden color and a lustrous surface, making it suitable for decorative applications.
Antibacterial Properties: Brass naturally inhibits bacterial growth, making it beneficial for machining parts requiring high hygienic requirements.
Non-magnetic: Brass is not attracted by magnets, making it suitable for certain industrial applications and recycling.
Low friction and good wear resistance: Brass has a low surface friction coefficient, making it suitable for applications such as machining moving parts and pipeline valves.
The Effect of Alloying Elements on Brass Properties:
Zinc: Affects brass’s color, strength, and workability and is the primary element in its formation.
Lead: Its addition improves machinability and corrosion resistance.
Tin: Enhances corrosion resistance, especially in marine environments.
Iron: Increases hardness and improves forging properties.
These properties, combined, determine brass’s machinability and formability during machining, as well as the durability and performance of the final part.
2.Common Brass Alloys
Common machining grades include C300, C360, C335, C314, C230, C272, and C220. The C3XXX series is considered a free-machining grade (with near-100% machinability).
The following table summarizes common machining grades, compositions, and key properties. Source.
| Brass Alloy Grades | Copper (%) | Zinc (%) | Lead (%) | Additional Elements | Key Properties |
| C260 (Cartridge Brass) | 70 | 30 | – | – | High ductility, corrosion resistance, good strength |
| C280 (Muntz Metal) | 60 | 40 | – | Iron (minor amount) | High corrosion resistance and good for casting |
| C230 (Red Brass) | 85 | 5 | – | – | High corrosion resistance and decorative appeal |
| C360 (Free Machining Brass) | 60 | 35.5 | 3 | – | High machinability and good formability |
| C385 (Architectural Bronze) | 59 | 42 | Up to 3.5 | – | Excellent machinability and high-precision work |
| C464 (Naval Brass) | 9 | 40 | – | 1% Tin | Marine corrosion resistance and durable |
3.What tools are used for brass turning?
The tools used in brass turning are mostly the same as those used for turning other metals. However, because brass is relatively soft and easy to cut, these tools are easily adapted for use with brass, and they can also be used to work other similar materials.
The most basic tool used in brass turning is called a “burr.” It is a conical grinding wheel used to remove material from the brass being turned. Burr wheels come in various sizes and shapes, some with diamond tips, others with flat or rounded edges.
Another common brass turning tool is a “grinding disc.” This tool is similar to a burr, but it has a dual function: one side cuts the metal surface, while the other is used for polishing or finishing to remove any marks left by the cutting operation.
Other types of tools used in brass turning include drills and reamers (for drilling holes), chucks (for securely holding the workpiece), sanding rollers (for surface grinding), and collets (for securing the cutting tool).
4.CNC Turning Methods for Brass Parts
In CNC machining, brass turning is commonly performed using three main methods: conventional CNC lathes, CNC turning centers, and Swiss-type CNC lathes. Each method has its own unique characteristics and is suitable for different types of part machining.
CNC Lathe
This method is the most common method for machining brass parts. The workpiece is secured in a chuck, and the tool is mounted on a toolholder. Single-point cutting tools are used to remove excess material, gradually forming the desired shape. CNC lathes can perform a variety of operations, such as taper turning, thread cutting, knurling, and grooving. The machining programs are typically imported and controlled by CAM files.
CNC Turning Center
Compared to conventional CNC lathes, machining centers offer more powerful capabilities. In addition to conventional turning, they can also perform milling, drilling, grinding, and tapping. The advantage of turning centers is that they can perform multiple operations in a single setup, resulting in high efficiency and improved machining accuracy. Depending on their configuration, they may have 3-, 4-, 5-, or even more-axis machining capabilities.
Swiss-Type CNC Lathes
Swiss-type CNC lathes are specifically designed for producing small, complex, and precise parts. Their unique guide bushing design effectively reduces workpiece vibration and deformation during machining, making them ideal for machining small, high-precision parts. Common applications include avionics connectors, medical surgical instruments, antennas, and micro fasteners.Their unique guide bushing design effectively reduces workpiece vibration and deformation during machining, making them ideal for machining small, high-precision parts. Common applications include avionics connectors, medical surgical instruments, antennas, and micro fasteners.
These three turning methods complement each other to meet the diverse needs of brass parts, from routine machining to high-precision, complex machining.
5.How to Turn Brass on a Lathe？
Machining brass on a lathe involves turning a brass bar and using cutting tools to remove excess material, thereby turning the brass into the desired shape and size. The following is the complete process and key elements of the process:
(1) Material selection and preparation
Brass is mainly composed of copper and zinc and has good machinability and corrosion resistance. Common brass alloys include C360 (free-cutting brass), C260 (brass cartridge), and C464 (naval brass). Selecting the right alloy type is crucial to ensuring machining quality.
(2) CAD/CAM design and programming
Before manufacturing, a three-dimensional model of the part is first created using computer-aided design (CAD) software to determine the dimensions, tolerances, and geometry. Then, computer-aided manufacturing (CAM) software is used to generate the machining paths and tool paths of the CNC machine tool to ensure the efficiency and accuracy of the machining process.
(3) CNC turning
The prepared brass bar is mounted on a CNC lathe for rotary cutting. Common types of turning include:
External turning: reducing the outer diameter of a workpiece to form a cylindrical shape.
Internal turning: machining a hole or cavity inside a workpiece.
Threading: cutting external or internal threads.
Face machining: machining the end face of a workpiece to ensure flatness.
CNC lathes achieve high-precision machining by precisely controlling cutting speed, feed rate, and tool path. For a visual overview of the process, you can watch our video “Processing Brass Parts on a CNC Lathe,” which I believe will be helpful.
(4) Tool Selection and Calibration
Tools and their calibration are crucial in CNC turning and play a key role in the entire machining process. Lathes are used to shape brass, and deburring wheels help remove material and polish the surface. Reamers are used to machine precise holes to ensure high precision in the final product. In addition, calibration of CNC lathes is essential to obtain the highest quality brass parts.
(5) Surface treatment and quality control
After processing, necessary surface treatments such as polishing and electroplating are performed to improve the corrosion resistance and aesthetics of brass turned parts. Quality control includes dimensional measurement, appearance inspection, and functional testing to ensure that the parts meet the design requirements.
6.5 Important Points to Keep in Mind When CNC Turning Brass
Material Properties Must Be Understood
Brass is relatively soft, ductile, and has low cutting resistance, making it easier to CNC turn than steel. However, different brass types vary significantly. For example, free-cutting brass (C360) is very easy to machine and rarely sticks to the tool, while lead-free brass is prone to burrs and surface unevenness. Be aware of the material characteristics before machining.
Proper Workpiece Clamping
When turning brass parts on a CNC lathe, the workpiece must be clamped securely, but not too hard, as this can easily leave indentations on the surface. For slender parts, a tailstock or support device should be used to secure the workpiece to prevent vibration or bending during turning.
Tool Sharpness is Key
When turning brass, sharp tools are essential. Commonly used tools include carbide inserts or high-speed steel inserts. A sharp tool ensures smooth cutting and produces a high-quality surface finish. If the tool is worn and blunt, it is prone to galling and scratches.
Match cutting parameters
Brass allows for high-speed cutting, generally allowing for higher speeds, resulting in a smoother surface. However, the feed rate and depth of cut should be kept within a reasonable range, as this can easily cause vibration and burrs. A “high-speed + light-cut” approach is often chosen to ensure both efficiency and part accuracy.
Pay attention to chip evacuation and cooling.
When turning brass, the chips are short and fine, easily spattering. Maintaining good chip evacuation channels is crucial to prevent chips from entangled in the tool and affecting surface quality. Dry cutting is generally acceptable, but when machining deep holes or turning large parts, it’s best to use coolant to help cool and flush the chips.
7.Uses of Brass Turned Parts
Brass turned parts are used in many industries, including:
Plumbing and plumbing: valves, fittings, connectors, faucet parts
Electrical and electronic applications: terminals, pins, contacts, connectors, sockets
Medical and diagnostic equipment: surgical instrument accessories, gas connectors, diagnostic equipment parts
Automotive and transportation: sensor housings, connectors, fuel injector parts, electronic connectors
Hydraulics and fluid control: hydraulic connectors, valve bodies, fluid control valves, seals
Computers and telecommunications: SIM card trays, coaxial connectors, antenna assemblies, motherboard pins
Architecture and decoration: door locks, hinges, handles, decorative screws
Construction and industrial machinery: fasteners, bushings, gears, transmission parts
Rifle ammunition and military accessories: cartridge cases, bullet bases, ignition parts
Heat exchangers and energy equipment: condenser tubes, heat exchangers, valve bodies, connectors
Brass turned parts are widely used primarily due to their excellent properties. Brass is easily machined into various complex shapes, offers excellent electrical and thermal conductivity, and is corrosion-resistant, strong, and has a long service life. These advantages enable it to meet diverse component requirements across various industries.
Xavier Brass Turned Parts Production Capabilities
Whether you need standardized industrial brass parts or custom-designed specialized components, Xavier offers reliable solutions. Equipped with advanced multi-axis CNC lathes, turning centers, and Swiss turning equipment, we can produce a wide range of complex parts with high precision. Our team of experienced engineers is always available to address unique design challenges and complex requirements.
★ Over 10 brass materials available
★ Over 10 CNC turning operations available
★ ISO 9001 certified
★ Over 15 years of CNC machining experience
★ Design optimization and manufacturability support
Simply upload your design drawings to receive a quick quote. Our engineers will work with you immediately to determine the best machining plan and provide an accurate price estimate.
Summary
To summarize, through the precision turning process, brass turned parts not only have excellent mechanical properties, but also show a beautiful appearance. In the modern manufacturing industry, the application of brass turned parts is more and more extensive, and its unique advantages are also increasingly prominent. Understanding and mastering the key technology of brass turned parts processing plays an important role in enhancing the competitiveness of enterprises.
FAQ:
How durable are brass turned parts?
CNC machined brass parts are generally very strong and durable. Their lifespan depends on the operating environment, but under normal conditions, they can last up to 25 years. They resist corrosion from harsh environments and saltwater, and they offer low friction and good thermal stability, ensuring long-term reliability.
What are CNC turned parts?
CNC turned parts are parts machined using a CNC turning process. During machining, the workpiece rotates continuously, and the tool gradually removes excess material until the desired axisymmetric shape is formed.
What are some common brass turned parts?
Typical brass CNC turned parts include bushings, fittings, valve stems, threaded rods, nozzles, and couplings.
How does the cost of brass turned parts compare to parts made from other materials?
Compared to aluminum, brass raw material is more expensive, but it offers advantages in corrosion resistance, strength, and service life. Compared to stainless steel, brass is easier to machine and has lower labor costs.
Therefore, overall, brass parts have a better balance between performance and cost.