3D printing is a modern manufacturing method for building solid objects using a digital file. To create an object with a 3D printer, you need to use an additive process. In this process, objects are built by stacking layers of material on each other until the product is final.

On the other hand, CNC manufacturing has an opposite process where excess materials are cut out to get to the final product. CNC machines are pre-programmed and controlled by computer software, which keeps the whole cutting process in check.

Even though both manufacturing techniques are used today, they have many differences. It’s not just the process that is different, but also the resulting products, their features, functionalities, and applications. Today we’re going to learn more about these differences.

Comparing 3D printing and CNC

Choice of material

CNC machines can work with many different materials, including metal alloys:

- Aluminum

- Copper

- Brass

- Steel

- And other alloys

They can also work with hardwoods, softwoods, machining wax, modeling foams, acrylic materials, and thermoplastics. Different materials require specific cutting tools which can be changed quickly.

3D printers have a narrower range of materials. For example, desktop 3D printers mostly work with thermoplastics like nylon, ABS, PLA, and resins. However, thermoplastics are often mixed with other types of materials like metal, wood, and ceramics.

How 3D printing and CNC are Used

3D printing is generally simpler than CNC manufacturing in terms of use. After preparing a file, the operator needs to choose supports, fill, and orientation. Once printing has started, there is no need for supervision, and the machine can work on its own until finishing the product.

On the other hand, CNC manufacturing requires more labor. The operator needs to choose and attach the right tools, adjust the rotation speed, designate the cutting path, and reposition materials during operations. CNC machining also involves several post-processing techniques that take time.

Level of Precision

Some CNC machines have positioning accuracies at 0.001 inches, with tolerance as low as 0.005 inches. On the other hand, a lot of 3D printer models can match this accuracy. However, given the fact that CNC machines can work on tougher materials, their accuracy is generally better.

This is because 3D printers can get deformed when exposed to excessive heat. Even though some 3D printers don’t have these issues, they are very inconsistent and can often be inaccurate.

Operational Speed

Given the fact that 3D printers and CNC machines work with different materials and work pieces, it can be difficult to compare their speed. In general, 3D printing operations take several hours, while a CNC milling task with a similar level of complexity and size will last a maximum of one hour.

CNC machines cut away materials more quickly from large blocks, while 3D printers often must slow down to precisely put layers in the right positions. In general, we could say that CNC machining is faster and that printers have a long way to go before they can catch up.

Level of Vibration and Noise

CNC machining can be extremely loud. When cutting down hard metal materials with a large tool, the noise can be so intense that operators need to wear noise-canceling headsets to avoid hearing loss. However, when working on wax models, a CNC operation has a mild noise. 3D printers always have quite a rattling noise, no matter what kind of materials are used.

Additionally, when working with wood or metal, CNC manufacturing also causes heavy vibrations, and you don’t want the machine to lean on a wall or a desk. Similarly to the low noise levels they produce, 3D printers cause negligible vibrations.

Clutter and Messiness

Given the fact that the whole process involves cutting down materials that are often large and tough, CNC machining can be extremely messy. There are often pieces flying around and small particles getting stuck on parts of the machine, as well as the surroundings.

There are enclosed versions, but this means that there is more material residue on the machine itself. 3D printers are designed to be tidy and clean. In the worst-case scenario, the operator will have to remove the thermoplastic material.

Applications

When it comes to application, these technologies overlap in many areas. Therefore, we will focus on areas where one technology excels or where only one can be used. CNC machines are a better option for manufacturing products and parts that need to be precise, heat-resistant, and robust.

3D printing excels in manufacturing more sensitive work pieces that have rare applications. This includes printing food, building, bio-printing or even space use. They are easier to use, require less space, and don’t create that much noise, and these advantages are often more important in various industries.

Price Differences

The price range of both CNC machines and 3D printers can vary depending on the brand, features, functionalities, and so on. However, the base price for a solid 3D printer is at $500 while getting a functional CNC machine will cost you $2000. CNC mills are larger machines that require more materials to be built. Therefore, their prices are higher.

CNC or 3D printing: Which one to choose?

There is no universal answer when choosing between CNC and 3D printing. It all depends on your application and understanding your operational needs. Here are some general rules that can help you make the right choice:

- CNC mills are better for high and medium quantities. They are best suited for machining simpler work pieces in terms of their geometry.

- 3D printers are better in applications where small quantities are needed. They excel in manufacturing more complex and sensitive work pieces.

- If you are space limited, then a 3D printer is a better option.

- CNC machining works better for tougher materials, even in lower volumes.

Conclusion

The choice between these two isn’t obvious. Both have their advantages and different applications. You need to consider your process, budget, materials, volume, and complexity to make the right decision.

Meta title: CNC or 3D Printing, Which One Should I Use?

Meta description: CNC mills and 3D printers are the most popular manufacturing technologies today. Here is some useful information that will help you choose CNC or 3D Printing.