CNC milling service
Quick-turn prototypes and production parts delivered in days.
Global prototype pricing with tariffs included.
ISO 9001:2015, ISO 13485, IATF 16949:2016, AS9100D certified. ITAR registered.
Xtproto CNC Milling Service
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.
- 30+ 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 3,000 square meters and is staffed by 180+ skilled machinists and production professionals, ensuring stable capacity and reliable delivery.
Xtproto's CNC Milling Materials And Surface Finishes
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.
CNC Milling Materials
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
CNC Milling Surface Finishes
We offer a variety of surface finishes options to meet fuctional,cosmetic, or performance requirements. For parts of cnc machining,common surface finishes include:
Standard: 63–125 RMS finish, ideal for most functional components.
Polishing: High-gloss, reflective finishes for aesthetic or low-friction metal parts.
Heat Treatment: Precision hardening and tempering to enhance material strength.
Anodizing: Superior corrosion resistance and decorative color options (Aluminum only).
Plating: Nickel, tin, gold, and silver coatings for enhanced conductivity and wear.
Chemical Conversion: Black oxide and chromate coatings for rust prevention and matte aesthetics.
For other custom finishing requirements, please contact us.
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
CNC Machining Industries & Applications
Robotics
Consumer electronics
Aerospace & Aviation
Automotive
Industrial machinery
Medical and Dental
Defanse
Energy
CNC Machining 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
The guidelines below outline recommended and feasible dimensions to help ensure efficient machining and reliable part quality.
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Minimum feature size: Recommended Ø 2.5 mm | Feasible Ø 0.50 mm
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Internal corners (radius): Recommended R 8 mm | Feasible R 0.25 mm
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Wall thickness: Metals ≥ 0.8 mm (feasible 0.5 mm) · Plastics ≥ 1.5 mm (feasible 1.0 mm)
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Holes: Standard drill sizes recommended; depth ≤ 4× diameter (feasible up to 10× diameter, Ø 0.5 mm)
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Threads: Recommended M6 or larger, length ≥ 3× diameter (feasible down to M2)
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 FAQ
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.