CNC Machining Part

Online CNC Machining Service for Custom Parts

Machined prototypes and production parts in as fast as 1 day. Request an online quote today.

Certifications

ISO 9001:2015 | AS9100D | ITAR Registered

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 AS9100-certified 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 cut solid plastic and metal blocks into final parts.

CAPABILITIES

DESIGN GUIDELINES

CNC Turning

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

CAPABILITIES

DESIGN GUIDELINES


CNC Machining Materials

 

Metals

 

Plastics

 

 

copper machined part

If you have any issues getting your guide, click here to download.

CNC Machining Design Guide

In this guide to CNC machining, you'll learn how to create efficient, manufacturable metal and plastic parts for prototyping and production.


Design Guidelines for CNC Machining

     
Maximum Part Size 22 in. x 14 in. x 3.75 in. 559mm x 356mm x 95.3mm
Minimum Part Size 0.25 in. x 0.25 in 6.35mm x 6.35mm
Tolerances +/- 0.005 in. +/- 0.13mm
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 on your quote.  
Text

Plastic and soft metals: Minimum width of 0.018 in. (0.457mm), depth of 0.0118 in. (0.3mm). Example text size would be 16 point Arial Rounded MT font.

Hard metals: Minimum width of 0.033 in. (0.838mm) and depth of 0.0118 in. (0.3mm). Example text size would be 22 point Arial Rounded MT font.

 

 

  • Maximum part size varies by material. View this table to see a complete listing of our maximum part sizes.
    US Metric
Maximum Dimensions Diameter 3.95 in. 100.33mm
Length 9 in. 228.6mm
Minimum Dimensions Diameter 0.16 in. 4.07mm
Length 0.05 in. 1.27mm
Wall Thickness 0.020 in. 0.51mm
Angle 30° 30°
Tolerances +/- 0.005 in. +/- 0.13mm

 

  • Small features may be allowed, but the diameter in any region should not be less than 0.030 in. (0.76mm). 
  • Sharp conical points are allowed; angles should be greater than 30 degrees. Walls thinner than 0.020 in. (0.5mm) typically do not survive the machining process


CNC machine factory floor

Machined Parts on Your Schedule

Our lead time options lend you flexibility. Need machined parts lightning fast? Select Expedite at checkout. Not in a rush? Choose Economy to save on cost. For reliable delivery on-time, select Standard. Your parts when you need them.


Why Choose Us for Custom CNC Machining?

Fast and Reliably Delivery
Iterate part designs quickly and accelerate product development with quick-turn parts. Our automated design analysis will help spot any difficult to machine features before your design is sent to the manufacturing floor and save you from costly reworks further down the product development cycle.

Manufacturing Analysis and Online Quotes
When you upload your 3D CAD file to request a quote, we'll analyze your part geometry to identify any features that may be difficult to machine such as tall, thin walls or holes that cannot be threaded.

Domestic Production and Support
Work with a trusted U.S.-based manufacturer and eliminate the risk of sending parts overseas. You can also call or email us at any time and we'll help with ordering parts, design feedback, material recommendations, and answer any questions.

Infinite Capacity
Eliminate downtime spent waiting for parts and safeguard in-house machining with on-demand relief and infinite manufacturing capacity.

Material Selection
We stock more than 30 engineering-grade plastic and metal materials that are suitable for various part applications and industries. Materials range from plastics like ABS, polycarbonate, nylon, and PEEK to aluminum, stainless steel, platinum, and copper.



cnc milling process creating custom metal part

cnc milling black plastic material block



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
turned metal cnc part

Have Complex Components for Machining?

Tighter tolerances down to ±0.0008 in. (0.020mm). Complete parts with no material left behind. Anodizing at scale. Our manufacturing network of premium suppliers at Hubs can help. Get an instant quote for up to 1,000 parts today. 


CNC Machining FAQs

How much does CNC machining cost?

Prices start around $65, but vary based on complexity, quantity and lead time. The best way to find out is to submit a 3D CAD model and get an interactive quote with design for manufacturability (DFM) feedback. Because we use proprietary software and automated fixturing processes, there are no up front non-recurring engineering (NRE) costs. This makes purchasing quantities as low as 1 to 200 parts cost effective. Prices compared to 3D printing are comparable to somewhat higher, but machining offers improved material properties and surfaces.

What types of threading options are available?

We offer UNF, UNC, and metric threads for machining along with coil and key inserts (but do not supply or install the inserts). These are available on both milled or turned CNC parts. View this page to see our complete threading options.

What is the maximum part size for CNC machining?

Maximum part size will vary based on your selected material. Our largest part size offered is 22 in. x 14 in. x 3.75 in. (559mm x 356mm x 95.25mm) and is available in Aluminum 6061 and 7075. View this table to see maximum dimensions by material.

 

 

Where can I learn more about CNC design?

We have a variety of resources on CNC machining and how to design parts for the process. Here are some of our favorites:

What are the advantages of CNC machining?

Product designers and engineers choose CNC machining to rapidly produce prototypes and production parts. The manufacturing technology offers a high level of precision, engineering-grade materials, quick-turn lead times.


Additional Links and Resources