
CNC Machining
Ideal for prototypes and low volume production parts (1 to 40+).
Request an online quote today.
CERTIFICATIONS
ISO 9001:2015 | JOSCAR
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
Plastics
- ABS
- Acetal
- Delrin (POM)
- HDPE
- Nylon
- PEEK
- PEI
- PET
- PE-UHMW
- PMMA
- Polycarbonate
- Polypropylene
- PPSU
- PS
- PTFE
- PVC
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. |
Metric | ||
Maximum Dimensions | Diameter | 75mm |
Length | 228mm | |
Minimum Dimensions | Diameter | 4mm |
Length | 1.27mm | |
Wall Thickness | 0.5mm | |
Angle | 30° | |
Tolerances | +/- 0.1mm |

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.
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

"We primarily use Protolabs to test new ideas...as we consider a potential design improvement, we want the ability to create parts and see how they perform as quickly as possible.”
Ready to Get Started?
Upload a 3D CAD file of your machined part and within a few hours we'll send you free design analysis and an interactive quote.

High Speed CNC Milling
Design for Speed
Following these design guidelines will result in an optimal and economical manufacturing time.
And
Design for Function
These features show off capabilities, but take longer to machine.