CNC Milling Services
Tight tolerances, complex geometries, and scalable production — from rapid prototypes to full-scale manufacturing.
ISO 9001:2015 • ISO 13485 • IATF 16949 • AS9100D
Xtproto CNC Milling Services
We are a modern, intelligent manufacturing facility specializing in fast and high-precision CNC milling services.
With advanced equipment, a wide range of material options, and a rigorous quality management system, we provide end-to-end solutions—from prototyping and low-volume production to medium- and high-volume manufacturing.
- Fast Turnaround:We can deliver as quickly as within one day, helping you shorten your product development cycle.
- Advanced CNC Milling Capabilities：We are equipped with 3-axis, 4-axis, and 5-axis milling machines, allowing us to produce both simple and complex parts.
- 130+ Engineering-Grade Materials：We offer a wide variety of material options, including metals, plastics, and composite materials.
- Quality Assurance：Parts are manufactured and verified to meet specified tolerances, ensuring functional accuracy and reliability.
- Factory Scale：
Our facility covers 16,0000 square feet and is staffed by 120+ skilled machinists and production professionals, ensuring stable capacity and reliable delivery.
High-Precision CNC Milling Services
Supporting everything from 3-axis milling to advanced 5-axis machining, we produce custom parts with tight tolerances and reliable precision.
3-Axis CNC Milling Services
4-Axis CNC Milling Services
5-Axis CNC Milling Services
State-of-the-Art Precision CNC Manufacturing Facility
160,000+ sq ft
Modern Production Facility
600+ CNC Machines
3-Axis, 4-Axis & 5-Axis Machining Centers CNC TurningSwiss Lathes · EDM · Grinding
25+ Automated Production Lines
Integrated Machining & Post-Processing
24/7 Customer & Engineering
Support Responsive Global Service
120+ Engineers
Process Engineering • DFM Support • Quality Control
500+ Skilled Employees
Dedicated to Precision Manufacturing
1M+ Parts Produced Annually
From Prototypes to Mass Production
Fast Lead Times
Prototypes in 1-7 Days
Production in 2-4 Weeks
Advanced CNC Capabilities
With over 600 state-of-the-art CNC machines, including 3-, 4-, and 5-axis machining centers, Swiss lathes, EDM, and grinding equipment, we are equipped to handle the most complex part geometries and precision components. Our multi-axis machines and versatile tooling setups allow even intricate surfaces, fine threads, and precise holes to be produced with tight tolerances, consistent finishes, and high repeatability. From small prototype batches to high-volume production runs, our advanced equipment and automated workflows shorten lead times, reduce errors, and ensure part consistency, giving clients faster design validation, smoother production, and reliable results.
Key benefits:
- Complex part capabilities – Multi-axis machining ensures precise curves and geometries
- Tight tolerances & consistent finishes – Minimizes rework, improves assembly success
- Prototypes and high-volume runs – Fast validation and efficient production at any scale
- Efficient & reliable – Modern machines and automation maximize speed without sacrificing quality
Engineering Excellence & Quality Control
Our team of 120+ experienced engineers specializes in process engineering, design-for-manufacturing (DFM) guidance, and stringent quality control. From prototype development to high-volume production, every project undergoes comprehensive engineering reviews to ensure designs are both functional and optimized for efficient manufacturing. Our engineers oversee every stage, including process planning, tooling selection, workflow optimization, and final inspections, minimizing defects and reducing rework. Using advanced inspection and testing technologies, we monitor critical dimensions and functional parameters throughout production to guarantee precision, consistency, and reliability in every batch. With this comprehensive technical oversight, clients can confidently accelerate design validation, prototype testing, and mass production, keeping their projects on schedule and on target.
Certified Quality Assurance
Precision is controlled at every stage of production. From raw material verification to final inspection reports, our quality system ensures consistent accuracy for both prototypes and mass production.
Inspection Equipment
With 30+ quality engineers and 20+ advanced inspection tools such as CMMs and optical measuring systems, we ensure accurate dimensions, reliable material analysis, and consistent product quality across all production runs.
Quality Control Process
Our quality control follows a structured process that begins with incoming material inspection, continues with real-time in-process control during machining, proceeds to first article inspection (FAI) for validation, and concludes with final inspection before shipment. Each stage is documented and fully traceable to ensure consistent precision and reliability.
Certifications
Our manufacturing facilities are fully compliant with international standards. Backed by our comprehensive Certifications, including ISO 9001, ISO 13485, ISO 14001, and IATF 16949, we ensure strict quality control, medical and environmental compliance, and automotive-grade process management — delivering consistent performance and continuous improvement across every stage of production.
Fast Delivery To Keep Your Projects On Schedule
We understand how critical lead times are for your projects. Whether it’s rapid prototypes, small batch runs, or full-scale production, our modern facilities and efficient workflows ensure your parts are delivered on time, keeping your project moving forward without delays.
In product development and manufacturing, lead time often determines project progress. We focus on minimizing part delivery cycles, offering rapid response from prototypes to full-scale production. Prototypes are typically completed within 1–7 days, enabling fast design validation and functional testing, so engineering teams can iterate without delay. Flexible small-batch production allows even low-quantity orders to be completed in just a few days, accelerating market testing or trial runs.
For high-volume production, our multi-axis CNC machines and automated production lines optimize tool paths and workflows to maintain high output while ensuring consistent precision. Strict production scheduling and advanced planning systems ensure that every order is completed on time, minimizing waiting and delays. Our rapid delivery capability delivers not only speed but also stable quality, allowing clients to keep their projects on schedule with confidence.
Proven Production Capacity
We produce over 1 million parts annually, demonstrating our extensive experience in handling projects of all sizes—from single prototypes to large-scale mass production. Our scalable production processes, combined with advanced machinery and skilled teams, allow us to deliver precision components efficiently, on time, and without compromising quality. This capability ensures clients across industries receive consistent, high-quality parts regardless of order size or complexity.
Machined Parts
Start Your CNC Machining Project
From rapid prototyping to full-scale production, our complete CNC machining services deliver precision, fast turnaround times, and competitive pricing to support your product development goals.
What Is CNC Milling And How It Works
CNC milling is basically one of the core processes used in modern CNC machining services. In simple terms, it’s a way of cutting material away from a solid block of metal or plastic until it becomes the exact shape you need.
The part is fixed securely onto the machine table, and everything is controlled by pre-programmed G-code. Once the program starts, the machine follows the instructions step by step, removing material with rotating cutting tools. With our 3-axis and 5-axis machines, we can handle straightforward parts as well as more complex designs that require tighter tolerances.
Plastic parts usually keep their natural milled surface, which may show light tool marks depending on the design. Metal parts can go through additional finishing processes like anodizing or chromate plating if needed. After machining, we inspect the parts, finish them according to your requirements, and package them carefully for fast delivery.
Xtproto's CNC Milling Materials
We support CNC milling for a wide range of metal and plastic materials, suitable for prototyping and low-volume production. If you do not see your required material listed, please contact us for availability.
Metals
- Aluminum
- Stainless steel
- Brass
- Copper
- Titanium
- Mild steel
- Alloy steel
- Tool steel
- Spring steel
- Bronze
- Steel
- Magnesium
Plastics
- ABS
- Polycarbonate (PC)
- Nylon
- Polypropylene (PP)
- POM
- PTFE (Teflon)
- PMMA (Acrylic)
- Polyethylene (PE)
- PEEK
- Bakelite
- Rubber
- Carbon Fiber
- HDPE
- HIPS
- LDPE
- PBT
- PPA
- PAI
- PET
- PPS
- PS
- PVC
- UPE
- Bakelite
- FR-4
Type Of CNC Milling Surface Finishes
We offer a wide range of surface finishing solutions to enhance durability, appearance, and functional performance of CNC machined parts.
Surface Finish Capabilities
With 3-, 4-, and 5-axis CNC machines, Swiss lathes, EDM, and grinding equipment, we provide stable, high-precision surface finish capabilities for a wide range of parts. Depending on the process and requirements, standard structural components can achieve Ra 3.2–1.6 μm for general functionality; assembly or friction surfaces can reach Ra 1.6–0.8 μm to ensure fit and motion performance; and high-precision sealing, sliding, or cosmetic parts can achieve Ra 0.8–0.2 μm, combining precision and aesthetics.
Each machining method has specific strengths: 3/4-axis CNC is ideal for most flat or simple curved surfaces, while 5-axis CNC can handle complex contours and multi-angle geometries for more uniform, refined surfaces; Swiss lathes provide high precision and consistency for internal and external diameters; EDM delivers Ra 3.2–0.8 μm reliably on hard-to-machine metals or complex shapes; and grinding, especially surface and cylindrical grinding, achieves Ra 0.4–0.1 μm ultra-precision finishes for sliding surfaces or highly precise planes.
Combined with advanced tooling, optimized process parameters, and optional post-processing such as polishing, anodizing, or plating, we ensure every batch of parts meets strict functional, assembly, and aesthetic requirements, demonstrating our professional capability and consistent performance in surface finishing.
CNC Milling Tolerances
| Category | Capability |
|---|---|
| Maximum Part Size | Milling: up to 80” × 48” × 24” (2,032 × 1,219 × 610 mm) Turning: up to 62” (1,575 mm) L × 32” (813 mm) Ø |
| General Tolerances | Metals: ±0.005″ (±0.127 mm) per ISO 2768 Plastics & Composites: ±0.010″ (±0.254 mm) |
| Precision Tolerances | Tight tolerances including sub ±0.001″, per drawing and GD&T |
| Minimum Feature Size | 0.020” (0.50 mm) (varies by geometry and material) |
| Threads | All standard threads supported; custom threads require review |
| Surface Finish | As-machined 125 Ra or better; additional finishes available |
CNC Milling Design Guidelines
| Feature | Recommended | Feasible |
|---|---|---|
| Minimum Feature Size | Ø 2.5 mm | Ø 0.50 mm |
| Internal Corners (Radius) | R 8 mm | R 0.25 mm |
| Wall Thickness | Metals ≥ 0.8 mmPlastics ≥ 1.5 mm | Metals ≥ 0.5 mmPlastics ≥ 1.0 mm |
| Holes | Standard drill sizesDepth ≤ 4× diameter | Depth up to 10× diameterMinimum Ø 0.5 mm |
| Threads | M6 or largerLength ≥ 3× diameter | Down to M2 |
Customers We Serve
We deliver high-quality manufacturing services to a rapidly growing global customer base. Our customers are located worldwide and represent a wide range of industries—from independent inventors and product designers to large-scale industrial, commercial, medical, automotive, and aerospace companies. We are committed to meeting your design and manufacturing needs and helping transform your ideas into reality.
Why Choose XTPROTO For CNC Milling？
High Precision & Consistent Quality：
Tight tolerances, repeatable accuracy, and standardized inspection processes.
Wide Material & Process Capability：
Support for metals, engineering plastics, and composite materials.
Fast Turnaround：
Short lead times for prototypes and low-volume production.
Engineering Support：
DFM review to reduce cost and improve manufacturability.
Scalable Production：
From one-off prototypes to low-volume production.
Reliable Partner：
Clear communication, strict quality control, and on-time delivery.
CNC Milling FAQs
What is CNC milling used for?
CNC milling is used to manufacture high-precision metal and plastic parts across industries such as automotive, aerospace, electronics, medical devices, and industrial equipment. It is commonly applied to functional prototypes, custom components, and low-volume production.
What are the disadvantages of CNC milling?
While CNC milling offers high precision and flexibility, it can have higher machining costs for complex parts due to longer cycle times and tool wear. CNC milling is also less efficient for very high-volume production compared to processes like injection molding or die casting.
Is CNC milling suitable for low-volume production?
Yes. CNC milling is highly suitable for low-volume production because it requires no tooling, offers consistent quality, and allows easy design changes without additional setup costs.
What is the difference between CNC milling and CNC turning?
CNC milling removes material using rotating cutting tools while the workpiece remains stationary, making it suitable for complex geometries, slots, and pockets. CNC turning rotates the workpiece against a stationary cutting tool and is ideal for cylindrical or rotational parts.
How much does CNC milling cost?
The cost of CNC milling depends on material selection, part geometry, tolerances, quantity, and surface finish requirements. CNC milling is cost-effective for prototypes and low-volume production, and an accurate price is best determined by reviewing your CAD files.
Request Your Free CNC Machining Quote Today
After receiving your drawings, our engineers will analyze your custom CNC machining parts right away. We actively work with you to clarify all details before providing a quote that is both economical and accurate.