CNC vs. 3D Printing: What's the Best Way to Make Your Part?

Among the many manufacturing processes we have at our disposal when making parts for products, CNC machining, and 3D printing are among the most common. But which of these methods makes the best part?

Here's a look at each method’s key differences and similarities to help you decide.

Overview of CNC Machining

CNC machining is a manufacturing process in which metal or plastic parts are cut from a block of material using a computer-controlled router.

The router is guided by a 3D model of the part that's been created using CAD software. CNC machining is well-suited for making complex, precision parts with tight tolerances.

How does It work?

The CNC machining process begins with the selection of a block of material that will be used to make the part. The partnership is then cut into small pieces used to make the individual parts.

The CAD model of the part is then used to create a 3D simulation of the piece that will be cut on the router. The simulation is used to generate 3CNC code, which is fed into the router's computer.

The 3D recreation makes 3CNC code which is utilized to drive the CNC machine. The CNC machine then starts removing material from the part until it has reached its final shape. At that point, any holes or cavities will be drilled and tapped as necessary before the function is complete.

After the 3D machining process, the part goes through a 3 post-machining process that cleans and polishes it until it reaches its desired appearance.

Essential Resemblance of 3D Printing vs. CNC Machining

● Both 3D printing and CNC machining are manufacturing processes that use a computer to control a machine.

● 3D printing and CNC machining can both be used to make complex, precision parts with tight tolerances.

● 3D printing and CNC machining can both be used to make tools and jigs.

● 3D printing and CNC machining are both excellent choices for prototyping parts.

● 3D printing and CNC machining can both be used to make fast, custom components.

● 3D printing and CNC machining are both excellent at making low-volume parts.

● 3D printing and CNC machining can sometimes be used interchangeably to make the same part.

● 3D printing and CNC machining are both outstanding at making low-volume parts.

Key Differences between 3D Printing and CNC Milling

1. 3D printing uses additive techniques, while CNC machining uses subtractive methods.

2. 3D printing has a lower degree of precision than CNC machining.

3. 3D printing is better suited for making small, complex parts, while CNC machining is better suited for making large, simple parts.

4. 3D printing is high speed than CNC machining.

5. 3D printing is more valuable than CNC machining.

6. 3D printing requires more post-manufacturing work than CNC machining.

Key Decision Elements When Choosing a Manufacturing Model

There are 5 key decision factors to consider When choosing between 3D printing and CNC machining.

- Complexity of the part: If the part is simple, 3D printing will likely be more efficient than CNC machining. If the part is complex, 3D printing won't be able to match CNC machining's precision or speed.

3D printed parts are suitable for quick prototypes but are not ideal for mass manufacturing.

- Size of the part: 3D printing can accommodate features with tighter tolerances if they're small enough. 3D printed parts may not have familiar enough tolerances to meet CNC machining demands, though 3D printing technology is constantly improving.

3D printed parts are best suited for projects that require many small, intricate parts.

- Material of the part: 3D printing can use a wider variety of materials than CNC machining. 3D printed parts are available in various types of plastic, metal, wood, and even rubber, depending on the 3D printer type being used.

CNC machined parts can only be made from metal or plastic.

- Quantity needed: 3D printing is faster and more cost-efficient than CNC machining when making one or two prototypes, but it quickly becomes more expensive as the quantity increases because 3d printers charge per build plate area, which gets more significant as the size of the 3d printed part increases.

CNC machining does not scale linearly with quantity, so it is less expensive when making many parts.

- Post-manufacturing work is needed to finish 3D printed parts: 3D printing requires much more finishing than CNC milling due to 3D printing's layer-by-layer additive process, which creates seams where layers meet, along with build lines and other visual artifacts that need to be removed in order for the 3d printed part to be fully functional in its application. CNC machining finishes parts by eliminating excess material until they are complete.

Benefits of CNC Machining Over 3D Printing

· When comparing 3D printing vs. CNC machining, 3D printed parts are 3D printed in successive layers. 3D printed components can warp, sag, discolor, and generally look unprofessional when the 3D printing process is not done correctly.

· 3D printed parts often need to be painted or otherwise post-processed before they're ready for use.

· CNC machining produces more robust components than 3D printing because CNC machines remove excess material rather than adding it as 3d printers do.

· This results in CNC machined products that are less likely to break under stress than 3d printed products, which have more surface area with the potential to crack under pressure if they aren't strong enough to handle it.

· 3D printing has been used as a manufacturing option since the 1980s, when 3D printers were invented. 3D printing is best suited for prototyping, while CNC machining has been specializing in mass manufacturing since its inception in the 1950s, well before 3d printers hit the market.

· 3D printers make individual models, but CNC machines can produce multiple parts simultaneously at a much faster rate than 3d printing.

· CNC machining offers better precision and tolerances than 3D printing for larger part sizes because 3D printed parts are built layer by layer with limited scope and no support material, resulting in tolerance issues due to layering artifacts like sagging or warping.

· 3d printed components that need to fit together must be designed with these limitations in mind. In contrast, CNC machined parts do not have 3D printing's tolerance issues because CNC machines allow for the X, Y, and Z-axis to be machined independently with no build lines or other 3d printing artifacts in their way.

Request a Quote for Your Part

Conclusion paragraph: As you may have guessed, the decision to use CNC machining or 3D printing is a tough one.

There are many key similarities and differences between these two methods of manufacturing that each has its own benefits and drawbacks. For example, if your part does not require intricate detail, then it’s probably better to go with 3D Printing as this process will be cheaper for you in most cases.

On the other hand, if your part requires a higher level of intricacy printing, then CNC Machining would be best suited for your needs. Its ability to provide more precision with every cut can make all the difference when working with small pieces.

Our team at Ares is happy to offer free quotes for your parts. Contact now to get started!