CNC Machines vs. 3D Printers - Which Should You Choose?

When it comes to manufacturing, CNC machines, and 3D printers are highly renowned and recognized machines. They provide convenience to manufacturers, enable intricate designs, and maximize overall benefits without significant additional costs.

Yet, the question remains: which option is the better choice? There is no clear-cut answer to this question.

Both technologies have their advantages and drawbacks, but we can take the best decision by taking into account various factors. In this article, we are going to compare CNC machines and 3D printers and discuss the most important considerations that you can take into account while determining the most suitable option for your needs.

CNC machine vs. 3D Printers: Subtractive and Additive Manufacturing

Before we go deeper into the discussion of CNC vs. 3D printers, you must understand the working of both machines and how they are used in the manufacturing process.

CNC (Computer Numerical Control) machines and 3D printers are widely employed technologies in manufacturing. CNC machining involves beginning with a solid block of material and utilizing a computer-controlled machine to selectively remove material until the desired shape is attained. This technique is referred to as subtractive fabrication.

On the other hand, 3D printing, also known as additive manufacturing, operates differently. It constructs a part by adding successive layers of material using a computer-controlled printer. This method minimizes material waste since it adds material rather than removing it.

Each machine possesses its strengths and weaknesses, and selecting the appropriate technology for a specific application relies on factors like the complexity of the part, the level of precision needed, and the properties of the materials involved. To further understand the distinctions between additive and subtractive manufacturing, let’s explore the fundamentals in the following sections: 

a) What is 3D printing?

3D printing, also known as additive manufacturing, is a widely recognized and versatile manufacturing method that offers various benefits and finds applications across industries. It involves creating objects by building them layer by layer, which grants greater flexibility and adaptability in design. Additionally, 3D printing is a quicker and recommended approach for rapid prototyping, especially for smaller production runs, as it offers faster turnaround times and cost savings.

It’s important to note that 3D printing encompasses multiple types, providing the freedom to select different materials, techniques, speeds, finishes, and printing costs. This versatility allows for precise customization to achieve desired project outcomes while considering various technical factors.

In modern industry, several methods are employed to achieve desired outcomes using 3D printing technology. Among these methods, the following techniques are widely used:

Binder jetting

Material injection

Material extrusion

Vat polymerization

Powder bed fusion

Direct energy deposition

Sheet rolling

There is a prevailing misconception surrounding 3D printing, suggesting that it is primarily limited to thermoplastics and similar materials. However, the reality is quite different today. The technology has advanced, enabling 3D printing of metals, biocomposites, ceramics, and various other materials. This expanded capability enhances the overall versatility of 3D printing.

The misconception regarding the exclusive use of thermoplastics arises because they continue to be the most commonly utilized material in 3D printing applications. One significant application is rapid prototyping, which involves testing design feasibility. Thermoplastics are particularly well-suited for this purpose due to their faster curing times and relatively lower cost.

Despite advancements in 3D printing technology, there are still certain restrictions when it comes to large-scale production. These limitations stem from factors such as costs and time needed. Nevertheless, the field of 3D printing is progressing quickly and holds immense promise for use in industries.

b) What is CNC Machining?

CNC machining is a sophisticated technique that replaces manual involvement in machining tasks. It employs a computer to precisely calculate the movement of the machine’s cutting tool, resulting in highly accurate outcomes. The process commences with a CAD model, which the computer interprets and converts into specialized languages known as G codes or M codes. These codes enable the CNC machine to fabricate the desired shape according to the given instructions.

In addition to its exceptional precision, CNC machining offers the advantage of repeatability, making it highly favorable in the industry. In contrast to traditional machining methods, which rely on the general skills of the operator, CNC machining eliminates variations in results caused by human performance fluctuations throughout the day. With CNC machines, computers take complete control of the system, requiring minimal human intervention.

The utilization of CNC machines brings forth a multitude of benefits, including enhanced efficiency, accelerated production speeds, and reduced costs with minimal risks. These advantages greatly enhance the practicality of this technology for businesses, and they contribute significantly to its widespread acceptance worldwide.

Key Similarities Between CNC Machining and 3D Printing.

While 3D printing and CNC machining are distinct technologies with different uses and methods, they do share key similarities. Both processes begin with a computer-aided design (CAD) model. In CNC machining, the model serves as a guide for generating G/M codes, whereas 3D printers utilize it directly to initiate the production of successive layers, forming the end product or component.

CNC Machining vs. 3D Printing: Which Is Best?

In the realm of manufacturing, it is widely understood that there is no universal solution that can address all production challenges across industries.

CNC machining and 3D printing are both effective options for tackling various manufacturing problems. However, it is difficult to definitively declare one as superior to the other. Each technology possesses its own set of advantages and disadvantages, which ultimately dictate the most suitable alternative for specific needs and circumstances.

Let’s take the example of 3D printers. They offer remarkable flexibility, enabling the creation of highly intricate objects. However, regardless of the number of pieces produced, the cost per piece remains constant. In contrast, CNC technology provides the opportunity to benefit from economies of scale, leading to significant overall cost reductions.

There are numerous other instances where both 3D printing and CNC machining can accomplish the task at hand. However, choosing between them becomes challenging and depends on factors such as time, budget, and technical considerations.

CNC Machines vs. 3D Printers: What Should You Consider Before Making a Choice?

Before starting production, product designers and engineers face a crucial decision: choosing the manufacturing method for their product. It’s essential to strike a balance between cost, speed, and accuracy to ensure optimal performance and maximum benefits. If one aspect is prioritized at the expense of others, the result may not meet the requirements. That’s why the design phase is resource-intensive, requiring careful consideration of technical factors and associated costs.

When comparing CNC machines and 3D printers, it’s important to consider factors beyond speed, time, and cost limitations. These are some of the key considerations for businesses deciding between the two technologies:

1. Choosing the right material for your CNC machining or 3D printing project is essential

The initial consideration, which is highly significant, revolves around material selection, as it remains a major technological constraint for 3D printers. Nowadays, 3D printers allow for the use of various materials, including metals and ceramics. However, limitations still exist concerning the overall mechanical properties of the printed parts.

For instance, 3D-printed metal parts may exhibit lower fatigue resistance and often require extensive heat treatment before they can be utilized. This can significantly increase the total cost and render the process impractical for your business. In such cases, CNC machines would be a more suitable option as they enable fast metal processing without necessitating heat treatment.

On the other hand, there are numerous materials where a 3D printer would be a preferable choice. Ultimately, the selection depends on the specific project details, requiring careful consideration of all related factors.

2. What is the anticipated quantity of production?

The expected production volume is another crucial factor that determines the suitable manufacturing machine for your needs. The manufacturing industry has long relied on the principle of economies of scale, where higher production quantities lead to increased profitability. Nowadays, both CNC machines and 3D printers play significant roles in volume production.

CNC machines offer automated production of parts with minimal human intervention, capable of operating continuously, 24/7. On the other hand, 3D printer is commonly used for creating prototypes and even complex molds for larger production volumes, utilizing methods like the casting process. However, when volume production is the primary consideration, most businesses opt for CNC machines due to lower overhead costs and the absence of additional processes involved.

3. What is the size or dimensions of the individual piece?

The size of the part is another critical factor to consider when choosing between CNC machines and 3D printers. Typically, CNC machines are capable of handling larger parts due to their size and capacity. On the other hand, 3D printers have limitations in terms of associated costs and feasibility for larger sizes. It is important to assess the specific details of your project to make an informed decision. However, as a general principle, CNC machines are often the preferred option for larger parts.

4. Required Quality of Finished Products

CNC machines excel in delivering superior surface finishes compared to 3D printers, especially under suitable conditions.

The primary factor contributing to this distinction is that 3D printers are primarily designed for prototyping purposes and may require additional post-processing. In contrast, CNC machines are specifically built to manufacture final products that are market-ready, thus offering more advanced surface finishing capabilities.

5. Speed of cutting

CNC machines typically have faster cutting speeds compared to 3D printers. However, the total manufacturing time is not solely determined by cutting rates. Factors such as machine startup time, pre-processing requirements, and other considerations also play a role in determining the overall speed of the process. Additionally, the size of the part being produced is a factor to consider.

As a general guideline, 3D printers are often faster for smaller parts because they can begin manufacturing the part immediately. On the other hand, CNC machining is a more suitable choice for larger parts due to its efficiency in handling larger workpieces.

6. Post-processing requirements

CNC machines are known for producing parts that are fully market-ready. In contrast, 3D printers have different applications, often used for prototyping or assisting in mold creation. For these purposes, a rough surface finish is often acceptable. However, if you intend to use the part for other applications, additional post-processing may be necessary to achieve the desired finish.

When it comes to 3D-printed metal components, there is an additional requirement for heat treatment. Due to the nature of the 3D printing process, these parts may lack sufficient resistance to fatigue and impact properties. Heat treatment helps improve the internal structure and overall performance, although it is still not on par with CNC parts in terms of quality and performance.

7. Your budget for manufacturing

Both CNC machining and 3D printing come with associated costs. For smaller and one-off parts, 3D printing is often the more cost-effective option. However, when it comes to volume production and consistent operations, CNC machining is the preferred choice.

To better understand this, let’s take the example of a car. The application demands the highest quality and technical standards. At the same time, it is crucial to find cost-effective solutions due to market competition and the basic principles of business viability. Additionally, considering the competitive landscape, it is important to have a process that is fast enough. If your competitors can produce 10 components at the same time it takes you to produce one, your business will suffer in terms of missed opportunities and potential revenue loss.

Regardless of the chosen method, both CNC machining and 3D printing require significant capital and operational expenses. For smaller parts, 3D printing tends to be more cost-effective. However, as production requirements increase or time constraints become tighter, the alternative may be true, and CNC machining becomes a more cost-effective option.

Yangsen - the best supplier of CNC machine 

Congratulations on your decision to proceed with your project! If you have decided to go with CNC machines then we are here to assist you in taking the next steps. Our cutting-edge manufacturing facilities and advanced technology ensure the delivery of high-quality CNC Machines that precisely meet your specifications. At Yangsen, we offer the following CNC machines:

Horizontal boring machines

CNC vertical machining center

Horizontal machining center

Gantry machining center

CNC drilling machine

Engraving and milling machine

Buy your CNC machine now and Let’s turn your project into reality!