CNC Machined Part

CNC Machining

Ideal for prototypes and low volume production parts (1 to 40+).

Request an online quote today.


ISO 9001:2015 | JOSCAR

Plastic and metal materials
CNC machines
Machined parts each month

CNC Machining Processes

Looking for a reliable, quick-turn supplier of machined plastic and metal components? With hundreds of CNC machines, our unmatched in-house capacity ensures your parts are shipped on-time, every single time. At Protolabs, our CNC machining facilities are designed for both rapid prototyping and low-volume production of end-use components.

CNC Milling

CNC milling is a subtractive manufacturing process that uses 3-axis milling and 5-axis indexed milling processes to rapidly cut solid plastic and metal blocks into final parts.



CNC Turning

CNC turning with live tooling combines both lathe and mill capabilities to machine parts with cylindrical features from metal rod stock.



CNC Machining Materials




  • Aluminum
  • Brass
  • Carbon Steel
  • Copper
  • Mild Steel
  • Stainless Steel
  • Titanium



  • ABS 
  • Acetal
  • Delrin (POM)
  • HDPE 
  • Nylon
  • PEEK
  • PEI
  • PET



  • PMMA
  • Polycarbonate
  • Polypropylene 
  • PPSU
  • PS
  • PTFE
  • PVC 

copper machined part

Design Guidelines for CNC Machining

Maximum Part Size

3 axis: 254mm x 178mm x 95mm

5 axis: 66mm x 73mm x 99mm

(Max size for Aluminium 559mm x 356mm x 95mm)

Minimum Part Size 6.35mmx 6.35mm
Tolerances Typically, Protolabs can maintain a machining tolerance of +/- 0.1 mm. Parts may be as thin as 0.5 mm in regions as long as nominal part thickness is above 1 mm. Maximum depth that can be milled is 50 mm from either side of part. For specific milling dimensions by material, see maximum part extents for machining.
Radii Sharp inside corners on a part will be radiused (rounded) as a natural result of the CNC machining process. Resulting radii will be identified before the part is milled.
Text • Recessed text should have a minimum stroke width of 0.5mm.
• The spacing between characters on raised text should be 0.5mm or greater.
• Minimum recessed text depth of 0.3mm.
• If design permits it, opt for recessed text versus raised.
Maximum Dimensions Diameter 75mm
Length 228mm
Minimum Dimensions Diameter 4mm
Length 1.27mm
Wall Thickness 0.5mm
Angle 30°
Tolerances +/- 0.1mm

CNC Threading

Threading Options and Guidelines

For machined parts, you can easily add threaded features, including key and coil inserts. These can be specified within your interactive quote. When a quote is returned, the 3D display will show which thread types are possible for each feature. Different threads (where possible) or no threads can be selected on a feature-by-feature basis.

Why Choose Protolabs for CNC Machining?

Advantages of CNC Machining

The subtractive process of CNC machining provides multiple benefits for both prototyping and low-volume production parts.

  • Precision and repeatability
  • Tight tolerances
  • Production-grade materials
  • Quick-turn parts within 1 day

CNC Machining Applications

CNC machining is widely used throughout the aerospace, medical, automotive industries for its ability to rapidly manufacture precise parts in production-grade materials. Typical CNC parts, include:

  • Housings and enclosures
  • Brackets
  • Fixtures for manufacturing
  • Gears and bearings
  • Internal mechanical components
  • Medical instrumentation

Have Complex Components for Machining?

Tighter tolerances down to ±0.020mm. Complete parts with no material left behind. Anodising at scale. Our manufacturing network of premium suppliers at Hubs can help. Get an instant quote for up to 1,000 parts today. 

Get Hubs Quote

What's in an Online CNC Quote?

Upload a 3D CAD file of your machined part and within a few hours we'll send you manufacturing analysis and an interactive quote. Within your quote you can modify materials and quantities and see pricing updates in real-time. Additionally, within your manufacturing analysis, you can assign threading with a click of your mouse.

Each CNC quote contains:

  • Real time, accurate pricing
  • Manufacturing analysis 
  • Threading assignments

CNC Cube

High Speed CNC Milling

Design for Speed

Following these design guidelines will result in an optimal and economical manufacturing time.


Design for Function

These features show off capabilities, but take longer to machine.

Learn More