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CNC MILLING SERVICE
Precision CNC Milling Direct from In-House Factory
CNC Milling Instant Quote
STEP | STP | IGS | DWG | DXF | PDF Files and More
MACHINING CAPABILITY
3/4/5AXIS
FACTORY AREA
80, 000 ㎡
TOLERANCE
±0.0002"
CERTIFIED
ISO
Why Choose Unionfab for Your CNC Milling Projects?
400+ CNC Machines for Reliable Capacity
With 400+ advanced CNC machines across six facilities, Unionfab can support everything from rapid prototypes to volume production. A wide material selection helps match your exact project needs.
Built for Demanding Industries
Our CNC machining experience spans automotive, medical, consumer electronics, industrial equipment, and more, helping us meet strict requirements for precision, materials, and delivery.
Fast Quotes, Faster Project Starts
Get competitive pricing and lead times in minutes through our online quoting system. Our rapid prototyping support helps you validate designs, optimize parts, and reduce production costs earlier.
Lower Costs Without Compromising Quality
Unionfab helps customers save up to 50% compared with many European and American CNC machining providers, while maintaining reliable precision and part quality.
Certified Quality You Can Trust
With ISO 9001, 14001, 13485 & IATF 16949 certifications, Unionfab follows strict quality control processes to ensure your parts meet specifications from prototype to production.
400+
CNC Centers
4
In-House Facilities
300+
Vetted Suppliers
2M+
Parts Made
±0.0002"
Tight Tolerance
1 Day
Fastest Turnaround
Visit Unionfab CNC Machining Factories Online
3 Axis Machining Factory
4 Axis Machining Factory
5 Axis Machining Factory
CMM Inspection Room
CNC Machining Technical Specifications
| Limits for nominal lengths | ISO 2768-m (Default) | ISO 2768-f |
|---|---|---|
| 0.5mm to 3mm | ±0.1mm | ±0.05mm |
| Over 3mm to 6mm | ±0.1mm | ±0.05mm |
| Over 6mm to 30mm | ±0.2mm | ±0.1mm |
| Over 120mm to 400mm | ±0.5mm | ±0.2mm |
| Over 400mm to 1000mm | ±0.8mm | ±0.3mm |
| Over 1000mm to 2000mm | ±1.2mm | ±0.5mm |
| Over 2000mm to 4000mm | ±2.0mm | - |
| Limits for nominal lengths | ISO 2768-m (Default) | ISO 2768-f |
|---|---|---|
| Up to 10mm | ±1° | ±1° |
| Over 10mm to 50mm | ±0°30' | ±0°30' |
| Over 50mm to 120mm | ±0°20' | ±0°20' |
| Over 120mm to 400mm | ±0°10' | ±0°10' |
| Over 400mm | ±0°05' | ±0°05' |
| Limits for nominal lengths | ISO 2768-m (Default) | ISO 2768-f |
|---|---|---|
| Over 3mm to 6mm | ±0.5mm | ±0.5mm |
| Over 6mm | ±1.0mm | ±1.0mm |
| ISO 2768-K (Standard & Default) | ISO 2768-H (Precision) | |
|---|---|---|
| Straightness and Flatness | As tight as 0.05 mm | As tight as 0.02 mm |
| Perpendicularity | As tight as 0.4 mm | As tight as 0.2 mm |
| Symmetry | As tight as 0.6 mm | 0.5 mm |
If your CNC machined parts are part of a larger assembly, we can hold tight tolerances for standard shaft and hole fits based on the ISO 286 system. Please specify the desired fit class on your 2D technical drawing. Common fits we machine include:
Clearance Fits (e.g., H7/g6): For moving parts like sliding bearings and pistons.
Transition Fits (e.g., H7/k6): For accurate location with slight interference, requiring light tapping to assemble.
Interference/Press Fits (e.g., H7/p6): For permanent assemblies requiring pressing or shrink-fitting.
| Finish Tier | Metric (Ra μm) | Imperial (Ra μin) | ISO Grade |
|---|---|---|---|
| Default As-Machined | 3.2 μm | 125 μin | N8 |
| Fine Machined | 1.6 μm | 63 μin | N7 |
| Precision / Smooth | 0.8 μm | 32 μin | N6 |
| High-Precision Grinding | * 0.4 μm | 16 μin | N5 |
| Lapped / Polished | * 0.2 μm | 8 μin | N4 |
| Mirror / Superfinished | * 0.1 μm | 4 μin | N3 |
| CNC Milling | CNC Turning | |
|---|---|---|
| Max Size | 4000 × 1500 × 600 mm (157.4" × 59.0" × 23.6") | Ø 200 × 500 mm (Ø 7.8" × 19.6") Length |
| Min Size | 5 × 5 × 5 mm (0.2" × 0.2" × 0.2") | Ø 2 × 2 mm (Ø 0.08" × 0.08") Length |
CNC Machining Materials
We provide a comprehensive range of CNC machining materials to meet the manufacturing demands of your most rigorous applications.
Nylon (MJF)
An advanced nylon material enabled by Multi Jet Fusion (MJF), delivering consistent mechanical properties, smoother surface quality, and higher efficiency for batch production.
Best for: End-use parts, batch production, and high-performance functional components
Nylon (MJF)
An advanced nylon material enabled by Multi Jet Fusion (MJF), delivering consistent mechanical properties, smoother surface quality, and higher efficiency for batch production.
Best for: End-use parts, batch production, and high-performance functional components
Nylon (SLS)
A durable and versatile nylon material produced by Selective Laser Sintering (SLS), offering excellent strength and design flexibility for complex geometries without support structures.
Best for: Functional prototypes, complex structures, and low-volume production
FDM Plastics
A cost-effective solution for producing durable and heat-resistant parts, FDM materials are suitable for structural and engineering applications.
Best for: Structural parts, high-temperature resistance
Elastomers
Flexible and rubber-like materials designed to provide excellent elasticity, impact resistance, and durability.
Best for: Flexible parts, seals, gaskets, wearable products, and shock-absorbing components
Nylon (MJF)
An advanced nylon material enabled by Multi Jet Fusion (MJF), delivering consistent mechanical properties, smoother surface quality, and higher efficiency for batch production.
Best for: End-use parts, batch production, and high-performance functional components
Elastomers
Flexible and rubber-like materials designed to provide excellent elasticity, impact resistance, and durability.
Best for: Flexible parts, seals, gaskets, wearable products, and shock-absorbing components
Finishing Options for CNC Milling
A mechanical surface treatment that bombards the part with fine glass beads at high pressure to remove tool marks and create a uniform, matte texture.
Best For:
Achieving a consistent, non-reflective aesthetic finish and hiding minor surface defects on consumer electronics, enclosures, or grip surfaces.
Aluminum
Lightweight yet strong, aluminum materials provide a great balance of mechanical performance and thermal conductivity, making them ideal for performance-driven applications.
Best for: Lightweight structures, aerospace parts, and heat-sensitive components
Titanium
A premium engineering material known for its outstanding strength-to-weight ratio, corrosion resistance, and biocompatibility for demanding environments.
Best for: Aerospace components, medical implants, and high-performance parts
Copper Alloy
Engineered for superior electrical and thermal conductivity, copper alloys are ideal for applications requiring efficient heat transfer and electrical performance.
Best for: Heat exchangers, electrical components, and cooling systems
Inconel
A high-performance nickel-based superalloy designed to withstand extreme temperatures, oxidation, and mechanical stress in harsh environments.
Best for: High-temperature applications, aerospace, and energy industry components
Quality Assurance & Inspection
We adhere to a strict multi-stage inspection protocol to ensure every part meets your exact specifications.
Full FAI Documentation: Every order includes a First Article Inspection report (upon request).
Precision Metrology: We utilize state-of-the-art CMM (Coordinate Measuring Machines), profilometers for surface roughness, and calibrated hand tools.
Traceability: All material certifications and heat treatment reports are archived and available for audit.
Standards Compliance: Our quality systems are aligned with international ISO 9001 standards, covering dimensional, geometric (GD&T), and material requirements.
For more details on our quality standards, check out our Inspection Checklist (including both standard and premium options).
FAQs About CNC Milling
What type of CAD files do you accept for CNC quoting?
At Unionfab, we support a wide range of 3D file formats to ensure smooth compatibility with our manufacturing systems. The most commonly recommended formats are STEP (.stp/.step) and STL (.stl). If your design is in another format (such as IGES, OBJ, or others), it can usually be processed as well, but we suggest converting it to STEP or STL for the best results. These formats help preserve critical design details and ensure a more accurate and stable printing outcome.
What is your Minimum Order Quantity (MOQ)?
Typically, many standard 3D printing orders are completed within 1–3 business days. However, the exact lead time depends on the part’s size, complexity, material, and quantity. For a precise timeline, we recommend uploading your design files so our team can provide a detailed estimate based on your specific requirements.
What is the typical lead time for custom CNC machined parts?
The formula below encompasses all cost components involved in an industrial 3D printing quote:
Total Cost = Printing Cost (Material Unit Price × Part Weight) + Complexity Surcharge + Post-Processing + Packaging + Shipping + Customs Duty
For detailed explanation of the cost items above, you can refer to our 3d printing cost guide.
Will my design and 3D models be kept confidential?
At Unionfab, we ensure quality through a strict end-to-end control process. This includes file checks before production, process monitoring, and final inspection to verify part accuracy and consistency. We can also provide inspection reports or additional quality checks upon request, and our facilities follow recognized quality standards to ensure reliable results.
If your project has specific quality requirements, our team will work closely with you to define and meet those standards.
Do you provide material certificates and inspection reports?
Absolutely. We understand the importance of your intellectual property. Unionfab follows strict data security protocols. We are happy to sign a Non-Disclosure Agreement (NDA) before you upload your files. Our internal platform is encrypted, ensuring that your designs are only accessible to the essential technical team involved in your project.
