When creating a new product or part, you can use two different tools, a CNC machine or a 3D printer. Both function well, are standard tools and have advanced to meet various production needs. However, you must understand how each one works to choose the most suitable one for your needs.
CNC machines are popular manufacturing tools for small to medium and big volume production. A CNC machine such as the carves out the needed components from a large chunk of material. It produces robust parts with precise dimensions, so it is popularly useful in manufacturing industries such as woodworking, engraving, lettering, engines, and machinery. To create a part, the user first designs a 2D or 3D model through computer-aided software. After inputting the instructions, they are converted into specific commands by a software program that sends them to the CNC machine for execution. A CNC machine uses tools such as saws and drills to make the needed cuts. Standard CNC machines include drills, mills, routers, laser cutters, plasma cutters, lathes, and grinders.
On the other hand, 3D printers are used in additive manufacturing that builds products from the bottom to the top by adding layers. It is mostly useful in the medical industry to create parts such as implants and prosthetics. The food industry also uses 3D technology to process foods by squeezing out food products layer by layer. Fashion designers and artists also use it to create art pieces. To create a part, the user first creates a 3D design using CAD or a 3D scanner. A 3D scanner analyzes the design and shape of the actual 3D item and creates a digital version from it. Photogrammetry software can also be used to analyze photographs and create 3D objects. The design is then analyzed to spot out any errors such as holes.
A program converts the 3D model into a series of 2D layers to prepare it for the 3D printer producing a G-code file with instructions for the printer to follow. The 3D printer reads the instructions and lays the material layer by layer to create a 3D final product. The printing procedure may take from hours to days, depending on the complexity of the project.
Common differences between CNC machines and 3D printers
Size of parts
CNC machines can make a wide variety of small and delicate parts to high-volume parts. A 3D printer cannot create a larger part than its printing bed.
CNC easily adapts to new material and works with a broad range of materials from metal, wood, plastic, acrylics, thermoplastics, wax, alloys, and modeling foam. With 3D printers, you can only use plastics, metals, and polymers.
CNC machines are faster in large-scale production because they use an assembly line of machines producing each part. On the other hand, printers process each piece from start to finish making it unsuitable for large-scale production.
CNC machines are highly heated tolerant making them achieve high accuracy and precision. 3D printers are still far from achieving that kind of precision.
CNC machines produced more polished parts since the materials do not get deformed during the process. 3D printers fail at times producing parts that tend to bend and warp.
The final take
Although CNC machines and 3D printers meet various needs, CNC machines are cost-effective, faster, and produce high-quality parts.