CNC Machining Vs. 3D Printing

3D printing and CNC machining methods are two manufacturing methods that have their specific features and advantages.

You must know each method and where these technologies can best to applied. We’re comparing these leading fabrication methods and technologies and their pros and cons to achieve the desired results.

What is CNC Machining? 

CNC machining is used in nearly every engineering industry to make precise, durable, and heat-resistant parts.

It offers great versatility, can work with any material, and has many applications. These machines give very accurate results for small production to bulk production.

CNC machining becomes highly demanding due to its accurate and cost-effective outputs and is mostly used for functional prototypes, testing, and engineering evaluation.

What is 3D Printing?

3D printing is a go-to process for manufacturing custom-designed and small-scale projects. It is suitable for those operations which require multiple prototypes with superior integrity.

3D is known as ‘additive manufacturing. A three-dimensional object is manufactured from a 3D or CAD model and offers a deep insight into the aesthetic and shape of the desired part.

It is best for minor-scale projects to save money on buying expensive molds.

In the era of 1980, 3D printing was used to manufacture functional and aesthetic prototypes. But recently, it has been discovered that it is a highly recommended procedure for manufacturing at the industrial level.

Advantages of CNC Machining

CNC machining is a demanding process to manufacture prototypes and produce more precise, reliable, and accurate components for worldwide industries.

1. The CNC machining process is vital in today’s world and makes the manufacturing process easy and efficiently affordable.
2. CNC machines are computerized machines that need no human supervision. So, the chance of human error is also eradicated. These machines rely on the instructions from the computer software that controls them.
3. It provides freedom to choose the resolution of manufacturing and low-cost machinery.
4. CNC machines are made to run for longer cycles without breaks to get high-quality output.
5. The material used in CNC machining is cheaper, making it better to manufacture superior quality precision and surfaces.
6. The CNC machining process is more reliable due to less waste, higher precision, and higher accuracy.
7. CNC machines limit energy consumption and give cost-effective outcomes for low and high-production methods.
8. Machines control all operations and functions, so there is no chance of negligence.
9. It makes the production of complex parts more convenient using a broad selection of materials.
10. It is more versatile due to the latest technology, automatic tool-changing capacity, and use of various tools on the same machine. Applications of CNC Machining

Advantages of 3D Printing

3D printing has many advantages as compared to other manufacturing methods. Some of them are summarized below:

1. 3D printing is known for very complex and intricate designs that other traditional manufacturing methods can not make.
2. 3D printing rapidly manufactures, thus making the prototyping process faster. Therefore, manufacturing takes a shorter time and is a cost-effective process.
3. As the 3D designs are stored virtually, there is no extra space acquired by inventory. These 3D designs stored virtually can be edited anytime at a lower cost.
4. 3D machining makes little to no waste, unlike other traditional manufacturing methods in which there is much unrecyclable waste. This factor also makes 3D printing a cost-effective process.
5. 3D printers are easily accessible now. And there is no difficulty of transportation like one faces while importing from other countries.
6. 3D printing is also an environmentally friendly process as it creates no waste.

Disadvantages of CNC Machining

Some major drawbacks of CNC machining are discussed below:

• CNC machining is an expensive technique because of the high cost of CNC machines.
• It increases the risk of unemployment because of the requirement for fewer workers to operate CNC machines. So expansion in CNC machining may lead to unemployment.
• No manually operated skills are required for this technique. Thus engineers lack the old engineering and mathematical skills resulting in skill loss.
• CNC machines being automatic machines, usually cost more than manually operating machines.
• In resolving a breakdown, only a highly trained and professionally skilled person is required to solve the issue.

Disadvantages of 3D Printing

Even though 3-D printing is a beneficial and advantageous method, there are also certain cons to this procedure. These are as below:

• 3D printing is not possible for a wide range of materials.
• Due to the small size of printing chambers in the process of 3D printing, you can only print small parts. If you intend to print a bigger part, it will cost more and take longer.
• Although the initial investment in 3D printing is lower than other traditional printing methods once scaled up for larger parts, its cost per unit cannot be expected to reduce as in the case of injection molding.
• In 3D printing, the parts are joined layer by layer, and they are more brittle than the parts in injection molding, where the parts are joined strongly.
• CNC machines control 3D printing technology. So, it can be a disadvantage for countries with a poor economy, leading to unemployment.
• The process of 3D printing can be disadvantageous of the fact that the final product can be different from the original design. And the recorrection will cost more and take more time as well.

Types of CNC Machines

CNC machining proved suitable for various industries, including automotive, aerospace, construction

Some types of CNC machines are:

• CNC grinder & CNC plasma cutter
• CNC milling machine & CNC laser cutter
• CNC router machine and drilling machine
• EDM (electric discharge machine)
• CNC lathe machine
• CNC water jet cutter

Types of 3D Printing

Various types of 3D printing are as follows:

• Stereolithography
• Poly Jet
• Electron beam melting
• Selective laser sintering
• Multi Jet Fusion
• Direct metal laser sintering
• Fused deposition modeling
• Digital light process

Applications of CNC Machining

• CNC machining is very effective in automotive or manufacturing industries where the metal removal process is involved. Metal removal machines typically employ CNC machining techniques.
• EDM also employs CNC machines to remove the metal by burning it with a spark.
• CNC machines are used in drilling, milling, and turning operations too.

Read More: Applications Of CNC Machined Parts In Various Industries

 Application of 3D Printing

3D printing is a technique that can be employed in every field. Some major applications of 3D printing are as below:

• 3D printing techniques are now employed in manufacturing, medical and sociocultural sectors. The manufacturing industries (aerospace and automotive) enjoy the benefits of 3D printing
• There are numerous applications of 3D printing in the field of medicine. These include bioprinting or prosthetics.
• 3D printing techniques are used in the construction components, such as power bonding, additive welding, and extrusion.
• 3D printing has applications in making jewelry by aiding the intricate designs with other jewelry-making methods and making it possible at a lower cost.

Differences Between CNC Machining and 3D Printing

1. CNC machining is a subtractive fabrication process, whereas 3D printing is an additive manufacturing method.
2. CNC machines produce a large amount of waste that is not recyclable. Whereas in 3D printing, there is little to no wastage, you would need not clean up anything.
3. In CNC Machining, you can speed up the production process, making many products in a shorter time. Whereas in 3D printing, it is not possible to speed up the process unless you buy a new printer that is faster.
4. CNC machines and 3D printing use various types of files that are incompatible with each other.
5. With CNC machining, you can produce larger parts easily. While in 3D printing, this is not easily achievable. You can print larger parts after breaking them into smaller parts, and printing takes more time and costs more.
6. CNC machines can work with materials like metals, alloys, and wood. It can use new materials. While on the other side, 3D printers work with a limited variety of materials like plastics or metals. 3D printers cannot work with new materials. They can only work with one material.
7. CNC machines are faster in production as compared to 3D printing machines. It gives more accurate and precise results.
8. CNC machining gives a smooth finish as compared to 3D printing. The final product in CNC Machining is perfect, but in 3D printing, sometimes the parts can be bent or warped.
9. CNC machining involves removing materials to produce new products. In comparison, 3D printing involves adding new materials to produce new products.

Similarities of CNC Machining and 3D Printing

Besides the differences mentioned above, there are some key similarities between CNC machining and 3D printing, which are listed below:

1. Both CNC machining and 3D printing make 3D products. These 3D products are based on a pre-designed 3D model.
2. CNC Machining, as well as 3D printing, is not a manual manufacturing method. Both processes are governed by computer software.
3. CNC machining and 3D printing are becoming more common in almost every industry.
4. CNC machining and 3D printing- both methods are compatible with STL and OBJ file types.
5. CNC machining and 3D printing are holding a leading position in today’s date.

When to Use CNC Machining and When to Use 3D Printing

When choosing a method for manufacturing your products, you must know the pros and cons of CNC machining and 3D printing.

There are certain circumstances where you should opt for CNC machining and some circumstances where you should go for 3D printing.

Some guidelines regarding choosing the right method are given below.

1. When planning to manufacture intricate and complex parts, you should choose 3D printing or additive manufacturing.
2. When you intend to make products that are specific, customized, or of particular geometry, you should go for 3D printing. 3D printing is also quite famous in dentistry, where it is used to make customized items for specific patients.
3. For large-scale production, which can be time-consuming, you should choose CNC Machining over 3D printing.
4. If you are interested in making several items of a small amount, 3D printing can be a better choice as it is highly known for quickly transferring jobs.
5. Regarding cost-effectiveness, there are two different perspectives on choosing the right method. In the case of 3D printing, the cost per unit remains the same. While in CNC machining, the cost per unit decreases with increased production. So if you want large-scale production, you should choose CNC Machining.
6. It would be better if you considered the complexity of the products, the cost per unit increases in the case of CNC Machining, while in 3D printing, it remains the same. So if you are looking to make complex products, you should choose 3D printing.
7. 3D printing is a slower method as compared to CNC Machining. In a quick comparison, 3D printing makes only one product in a period during which CNC machining makes a hundred.
8. The process you choose also depends upon the materials you are using and where the final product will be used.
9. CNC machining is better if heavy metals, wood, and plastics are used. They will use engines, automobiles, and components that must be highly strong and resistant to heat.
10. 3D printing is a good choice if the materials include plastics or resins.

Conclusion

In this article, you have learned about CNC machining and 3D printing, their differences, and their similarities. Although 3D printing is a modern technique, CNC machining is more advantageous if you consider the speed, accuracy, cost, or time.

It means 3D cannot replace CNC machining at any level. 3D printing offers more benefits for small-scale production, but the large-scale CNC machining method is undoubtedly unbeatable.