CNC Machining Service

Choosing the right CNC machining service involves considering several factors that will ensure your project is completed successfully. Key considerations include:

• Capabilities and Equipment: Ensure the service provider has the right machinery and tooling capabilities (e.g., 3-axis, 5-axis, CNC turning, or milling) for your specific part design.

• Material Expertise: Check if they have experience working with the material you require, whether it’s metals, plastics, or composites, and whether they offer the necessary material certifications.

• Tolerance and Accuracy: Review their precision capabilities. For high-precision projects, make sure they can meet your required tolerances.

• Turnaround Time and Lead Time: Consider how quickly they can produce prototypes or full production runs. A reliable CNC service should meet tight deadlines without compromising quality.

• Cost and Volume: Compare prices for one-off prototypes vs. high-volume production. Ensure they provide competitive pricing and can scale with your project’s needs.

• Support and Communication: Effective communication and a collaborative design process can make a big difference in achieving the best outcome. Choose a service provider that offers ongoing support and is responsive to your needs.

At KingStar Mold, we specialize in delivering high-quality CNC machining solutions tailored to your project’s needs. From prototype to mass production, we provide personalized service, precision, and industry expertise.

CNC milling and CNC turning are both key machining processes but differ in the way the workpiece is manipulated.

• CNC Milling involves rotating the cutting tool while the workpiece remains stationary. This allows for a range of cuts, including drilling, contouring, and creating pockets. It’s typically used for parts that require complex shapes or multi-dimensional features. Milling is especially ideal for parts with flat surfaces or intricate geometries.

• CNC Turning uses a rotating workpiece while the cutting tool remains stationary. This process is best suited for cylindrical parts and round components like shafts, bolts, and bushings. It excels in high-volume production runs for parts that only require axial symmetry.

The main difference lies in how the part and tool move, and the choice between the two depends on the part shape, desired features, and machining time.

Why CNC Machining Is Well-Suited for Complex Geometries

• Multi-Axis Machining Capabilities

Modern CNC machines operate on 3, 4, or 5 axes (and sometimes more). This allows them to approach the workpiece from multiple angles, enabling the creation of undercuts, intricate contours, compound curves, and deep cavities — all in a single setup.

• High Precision and Repeatability

CNC machining offers exceptional accuracy (often within ±0.01mm for metals and ±0.05mm for plastics). This level of precision is ideal for geometries with tight tolerances or intricate features such as mating parts, interlocking designs, or functional assemblies.

• Toolpath Flexibility

With advanced CAM (Computer-Aided Manufacturing) software, toolpaths can be precisely optimized to navigate tight internal corners, complex cutouts, and non-linear shapes. This is especially effective when combined with small-diameter cutting tools.

Key Considerations for Complex CNC Designs

Even though CNC machining is capable of producing complex parts, certain design factors can impact manufacturability and cost:

• Internal Corners

CNC tools are round, which limits the creation of perfectly sharp internal corners. To accommodate this, designers should apply fillets (radius) to internal edges. Larger radii are easier and cheaper to machine.

• Deep Cavities and Thin Walls

Creating deep, narrow cavities increases tool deflection and vibration, which can reduce dimensional accuracy. Similarly, very thin walls may chatter or warp. To avoid this:

• Limit depth-to-width ratios (preferably ≤ 4:1)

• Keep wall thickness ≥ 0.8 mm for metals, ≥ 1.5 mm for plastics

• Undercuts and Reverse Angles

These features are not accessible with standard 3-axis machines. However, they are achievable using:

• 5-axis machining

• Specialized tooling

• Multiple setups or EDM (Electrical Discharge Machining) for extreme cases

• Small Features and Holes

Tiny holes, threads, or intricate slots are possible but may require micro tools or secondary operations. Be aware that:

• Holes smaller than Ø1.0 mm can be difficult to maintain in metals

• Custom or fine threads may require thread milling or tapping tools with longer cycle times

Materials and Their Machinability for Complex Parts

Different materials react differently under complex machining:

• Aluminum: Excellent machinability for detailed features and thin-walled parts

• Titanium or Stainless Steel: High strength makes them more challenging, requiring slower feeds/speeds

• Plastics (e.g., PEEK, POM): Easier to machine but prone to thermal expansion or deformation during tight-tolerance work

Examples of Complex CNC Machined Parts

CNC machining is widely used for:

• Aerospace brackets with weight-saving cutouts

• Automotive components with intersecting bores and precise mating surfaces

• Medical implants with organic shapes and fine threading

• Robotics parts with interlocking geometries and assembly interfaces

KingStar Mold’s Capability in Complex CNC Projects

At KingStar Mold, our advanced 5-axis machining centers and precision fixturing allow us to handle highly complex parts with tight tolerances. From prototype to production, we specialize in:

• Multi-angle contouring

• High-precision pocketing

• Surface blending and aesthetic curves

• Small, intricate feature machining

Our engineering team is also available to help optimize your CAD design for manufacturability without sacrificing functional performance.

CNC machining is one of the most versatile manufacturing processes, capable of shaping an extensive range of materials into highly precise and durable parts. The choice of material directly affects the performance, cost, finish, and complexity of the part, making material selection a critical step in product development.

Below, we explore the most commonly CNC machined materials—grouped by metals and plastics—along with their typical properties and applications.

CNC Machinable Metals

• Aluminum

Aluminum is one of the most widely used CNC metals due to its excellent machinability, high strength-to-weight ratio, and corrosion resistance.
Common Grades: AL6061, AL7075, AL2024
Applications: Aerospace parts, automotive components, enclosures, heat sinks

• Steel

Steel offers high strength and hardness, making it ideal for load-bearing or wear-resistant components. It’s less corrosion-resistant than stainless steel but more affordable.
Common Grades: 45#, 1018, 4130, Tool Steel, Spring Steel
Applications: Machinery components, shafts, gears, tools

• Stainless Steel

Stainless steel is known for its excellent corrosion resistance, strength, and good aesthetics. However, it is harder to machine than regular steel.
Common Grades: SS304, SS316, SS303, SS410
Applications: Medical devices, aerospace parts, food processing equipment

• Copper

Copper is soft but extremely conductive, both electrically and thermally. Its machinability is moderate, and it’s often used in electrical applications.
Common Grades: Pure Copper, Brass, Bronze, Beryllium Copper
Applications: Heat exchangers, terminals, electrical contacts

• Titanium

Titanium is strong, lightweight, and highly corrosion-resistant, though it is one of the more challenging materials to machine due to its hardness.
Common Grades: Grade 2, Grade 5 (Ti6Al4V)
Applications: Medical implants, aerospace parts, high-performance components

CNC Machinable Plastics

• ABS

ABS is a low-cost, rigid plastic with good toughness and impact resistance. It’s easy to machine and ideal for prototyping.
Appearance: White, black, cream
Applications: Housings, covers, automotive trims

• POM (Delrin/Acetal)

POM is a high-strength, low-friction plastic with excellent dimensional stability.
Appearance: Black, white, blue
Applications: Gears, bearings, bushings, automotive components

• Nylon (PA)

Nylon is flexible, wear-resistant, and often reinforced with glass fibers for added strength.
Appearance: Natural, black, or reinforced variants
Applications: Washers, bushings, electrical insulators

• Polycarbonate (PC)

PC is strong, transparent, and impact-resistant, making it suitable for mechanical and optical applications.
Appearance: Transparent, black
Applications: Lenses, enclosures, light covers

• PTFE (Teflon)

PTFE is chemically inert, slippery, and temperature-resistant, but it’s also soft, which can make precision machining difficult.
Appearance: White, grey, black
Applications: Seals, insulators, non-stick parts

• PEEK

PEEK is a high-performance thermoplastic with excellent thermal, mechanical, and chemical resistance.
Appearance: Beige, light brown
Applications: Aerospace parts, medical instruments, electrical insulators

• HDPE

HDPE is lightweight, corrosion-resistant, and easy to machine.
Appearance: White, black, other colors
Applications: Fluid tanks, piping components, food-grade parts

How to Choose the Right CNC Material

When selecting a material for CNC machining, consider the following factors:

• Mechanical Requirements: Will the part experience high loads, friction, or impact?

• Environmental Conditions: Exposure to heat, moisture, UV, chemicals, or corrosion?

• Aesthetic Needs: Is the surface finish or color important?

• Cost Constraints: Some high-performance materials can be expensive.

• Regulatory Requirements: Medical, food-safe, or flame-retardant certifications?

KingStar Mold’s CNC Material Capabilities

At KingStar Mold, we offer CNC machining for a full spectrum of materials—from aerospace-grade metals to engineering plastics. Whether you need low-volume prototypes or high-precision production parts, we help you select the best material to meet your design, performance, and cost requirements.

With our extensive stock, professional machining expertise, and 24/7 engineering support, KingStar Mold ensures your parts are manufactured to exacting standards, every time.