The factory will conduct cable maintenance from 8:00 on Nov 9th to 2:00 on Nov 10th (GMT+8), and the production and delivery of orders will be delayed by 1 day.

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Overview: How CNC Milling works?

The Basics Of CNC Mills

CNC mills are automated cutting machines using a rotating spindle-head to cut away unwanted material. CNC milling machines come in a variety of sizes and different axis configurations. They are mainly utilized to cut harder metals but can work with workpiece materials ranging from plastic and aluminum to stainless steel and titanium.

How Does CNC Milling Work?

Use a multi-point rotating tool to remove material from the workpiece.It starts by fixturing a block of metal or plastic material inside the CNC mill. Using G-code, the CNC machine is programmed to rapidly mill out parts from the block of raw material.Basic mills consist of a 3-axis system (X, Y and Z), which is still one of the most popular and widely used machining processes. In 3-axis machining, the workpiece remains fixed, and the rotating tool cuts along the x, y, and z axes. Meanwhile, most newer mills can accommodate two additional axis, 4-axis CNC machining and 5-axis CNC machining have higher versatility, and they are often used in the production of high-precision parts.

CNC milling
The creation of these aforementioned features requires a variety of different milling operations:
  • Surface milling
  • Face milling
  • Angular milling
  • Form milling
  • Profile milling
  • Gear milling, etc.

Machined plastic parts are left as-milled, which typically means they show visible tool marks. Some metal parts allow more finishing choices like anodizing and chromate plating. When the run is complete and your required surface finish is applied, parts are boxed and shipped shortly thereafter.

Other Benefits Of CNC Milling

CNC milling

CNC milling machines are built for precise manufacturing and repeatability which makes them perfect for rapid prototyping and low-to-high volume production runs. CNC mills can also work with a variety of materials from basic aluminum and plastics to more exotic ones like titanium — making them the ideal machine for almost any job.

Features of CNC Machining

Advantages
Rapid Turnaround
Using the latest CNC machines, PCBWay produces highly accurate, quick turn parts in as fast as 2 day. We also instantly quote CNC machined parts, cutting days off of your RFQ process.
High Precision Tolerances
Offers high-precision tolerances ranging from +/-0.001″ – 0.005″, depending on customer specs. We are the experts in making parts that are truly custom and ready to use.
Scalability
CNC Machining is perfect for prototyping and production production parts. PCBWay's massive scale can help you scale up from testing phase to production runs of 100,000 parts of more.
Custom Surface Finishes
Suitable for many different kinds of substrates, make your parts just the same as real products.
Material Selection
Choose from over 50 metal and plastic materials. CNC Machining offers a wide variety of certified materials.
Cost Saving
Low investment in tooling and preparation costs, economical for parts with simple structure.
Drawbacks
Structure Limits
Interlocking and hollowed structure is difficult to be machined with CNC.
Scale Effect
The unit cost and lead time will not be reduced as much as injection molded parts.

CNC Machining Materials

Aluminum Steel Copper / Brass / Titanium / Zinc
2A12 201 Copper
5052 303 Brass
7075 304 Titanium(Ti)
6061 316 Zinc(Zn)
others 430 Mild steel(Low Carbon Steel)
- - Alloy steel
- - Tool steel
Plastics Others
ABS Bakelite
Transparent ABS Rubber
Polycarbonate (PC) FR4
Acrylic (PMMA) Others
Delrin/Acetal (POM) -
Polyethylene (PE) -
PTFE (Teflon) -
PEEK -

Custom Sourced Materials

A variety of CNC machined metal and plastic part options are available for an instant online quote. If you do not see the material stock you are looking for, please choose "Custom" under the material drop-down on your quote page and submit for an expert engineering review once you have specified features, tolerances, inspection needs, and quantities required.

Our standard surface finishes

Here is a list of standard surface finishes. For custom surface finishes such as electroplating or polishing, please contact sales@pcbway.com.
As-Milled
The finish option with the quickest turnaround. Parts are left with visible tool marks and potentially sharp edges and burrs, which can be removed upon request. Surface finish is comparable to 125 uin Ra finish.
As-Milled
Bead Blast
Abrasive blasting, more commonly known as sandblasting, is the operation of forcibly propelling a stream of abrasive material against a surface under high pressure to smooth a rough surface, roughen a smooth surface, shape a surface or remove surface contaminants.
Requirement Specification
Grit #120
Color Uniform matte of raw material color
Part masking Indicate masking requirements in technical drawing
Bead Blast
Anodized (Type II Or Type III)
Type II creates a corrosion-resistant finish. Parts can be anodized in different colors—clear, black, red, and gold are most common—and is usually associated with aluminum. Type III is thicker and creates a wear-resistant layer in addition to the corrosion resistance seen with Type II.
Requirement Specification
Grit #120
Color Uniform matte of raw material color
Part masking Indicate masking requirements in technical drawing
Anodized (Type II Or Type III)
Bead Blasting + Anodizing color or clear (type II)
Type II anodizing is mainly used to produce parts with a uniform, aesthetically pleasing surface and provides good corrosion and limited wear resistance. Parts are bead blasted to #120 grit prior to anodizing.
Requirement Specification
Thickness 8 - 12 μm (clear), 4 - 8 μm (color)
Color Black, clear or any RAL code or Pantone number
Part masking Indicate masking requirements in technical drawing
Bead Blasting + Anodizing color or clear (type II)
Powder Coat
This is a process where powdered paint is sprayed onto a part which is then baked in an oven. This creates a strong, wear- and corrosion-resistant layer that is more durable than standard painting methods. A wide variety of colors are available to create the desired aesthetic.
Requirement Specification
Thickness 18 - 72μm
Color Black or any RAL code or Pantone number.
Part masking Indicate masking requirements in technical drawing.
Powder Coat
Electropolished
Electropolishing is an electrochemical process used to polish, passivate and deburr metal parts. It is useful to reduce surface roughness.
Requirement Specification
Color Natural metal color.
Part masking Indicate masking requirements in technical drawing.
Electropolished
Brushed
Brushed or dull polished metal is metal with a unidirectional satin finish. It is produced by polishing the metal with a 120–180 grit belt or wheel then softening with an 80–120 grit greaseless compound or a medium non-woven abrasive belt or pad. Commonly brushed metals include stainless steel, aluminium and nickel.
Requirement Specification
Surface roughness 0.8 - 1.5 μm
Grit #80-120
Part masking Indicate masking requirements in technical drawing.
Brushed
Custom
Don’t see the finish you need? Submit an RFQ and we’ll look into a finishing process for you.

CNC General Tolerances

Unless we have agreed to other tolerances in your Quote, we will work to achieve and hold the tolerances noted below, which will vary per the primary manufacturing method you select.(eg.:Round hole 10mm, tolerance +0.01—0.03mm)

Description General Tolerance
Distance Dimensions For features of size (Length, width, height, diameter) and location (position, concentricity, symmetry) +/- 0.005”.
Orientation and Form Dimensions 0-12" +/- 0.005", Angularity 1/2 degree. For 24" and beyond please consult PCBWay's Manufacturing Standards.
Edge Condition Sharp edges will be broken and deburred by default. Critical edges that must be left sharp should be noted and specified on a print.