Thanks to technological advancements, there are numerous types of production machines and techniques, many of which can now be used and performed in someone’s own home. Perhaps the two most popular production methods these days are computer numerical control (CNC) machining and 3D printing. While these types of machines have many similarities, they do have significant differences and are used for unique purposes.
Subtractive vs. Additive Methods
CNC machining is considered a subtractive method of manufacturing. This is because these machines use tools, such as cutters, to remove parts of wood, metal, or other materials in order to produce a precisely shaped material. On the other hand, 3D printers work by layer materials to build a specifically designed product. This process is considered an additive method of production.
CNC machines can work with a wide variety of materials. These include aluminum, steel, brass, copper), hardwoods, thermoplastics, acrylic, and foams.
3D printers may be restricted to a select number of materials, such as resins and thermal plastics. While these materials can be made with metal and wood, the resulting work pieces may not be as robust as one cut directly from a heavier material when using a CNC machine.
In general, CNC machines like mills are typically more precise than desktop 3D printers. This is because a CNC machine is designed to cut parts with far more precision. While some 3D printers can be manipulated to be quite precise, their CNC machine counterparts tend to be better overall when it comes to precision cutting and design.
CNC machines and 3D printers use different materials and produce different items in most cases. But results have shown that a CNC mill can produce a work piece within just an hour, while it can take a 3D printer several hours to produce an object of comparable complexity and size. In addition, a CNC mill tends to chip away at a particular material faster than it takes a 3D printer to build an item with layers.
How Messy The Processes Are
CNC machines can produce a good amount of materials that spurt away from the machines. Working with metals can result in sharp pieces that come off the machine. Plus, not every CNC machine is completely enclosed. 3D printers are not quite as messy during the production process, although the print bed may need to be cleaned out at times.
On a related note, 3D printing does not result in as much waste as CNC machining. 3D printers only require the exact amount of material needed to produce an object. CNC machines must cut a large block or slab of a material, and most of any excess material cannot be reused or recycled.
What Can Be Produced
There are several similarities in terms of what CNC machines and 3D printers can produce despite how they are designed and the types of materials they can manipulate. To produce extremely precise and robust work pieces, CNC machining is the method of choice. The concept of 3D printing has more exotic fields in which it can be applied. These include bioprinting, printing food, building projects, and in the aerospace field.
3D printers are often cheaper to purchase. Some cost only a few hundred dollars. CNC machines can cost a few thousand dollars for a very basic machine.
Which Is Truly Better?
It is difficult to say whether a CNC machine is better than a 3D printer, or vice versa. Each machine is unique and can be used for a different production process. Novice manufacturers or hobbyists who produce items at home may find 3D printers more affordable and easy to understand. However, CNC machines are extremely efficient and precise, so they are often the better choice in certain cases.