CNC machining is a common material reduction manufacturing technology, different from additive manufacturing, CNC machining usually starts with a solid block and uses a sharp rotating tool to cut the material into a required shape. And 3D printing is a additive manufacturing process that develop from nothing.
Material
CNC Machining: Mainly used for processing metals, as well as softwood and hardwood, thermoplastics, acrylics, modeling foams and waxes. Each material needs a different cutting tool.
3D Printing: Metal, ceramic, wax, sand and composite materials.
Efficiency
CNC Machining: CNC machines can cut materials and machined parts faster than 3D printers. However, there is a need for extensive process planning and setup through a computer, especially when multiple processing steps are required, the parts often need to be repositioned. However, there is a need for extensive process planning and setup through a computer. Especially when multiple processing steps are required, the parts often need to be repositioned.
3D Printing: It can realize one-time forming, which means that, in addition to post-processing, it is not dependent on other manufacturing stages, but the problem is that the whole speed is slower, it can be achieved batch manufacturing such as SLS and SLM for many processes.
Precision
CNC Machining: Precision is determined by the geometry of the cutter, because all cutter have a machining internal angle with a radius. It can be produced the shape features smaller than the tool size, such as the wall is thinner than the diameter of the tool. Compared to the surface quality of 3D printing, CNC machining is better.
3D Printing: Product sizes are usually determined by the diameter of the material transport mechanism or by the diameter of the machine light spot (such as sintered laser or UV light source). The thickness of FDM printing layer is 100-20 00 microns, and the material jet printer can operate at resolutions as low as 16 microns.
Process
CNC Machining: Operators or engineers need to consider tool selection, spindle speed, approach position, angle, and path of cutting. These factors have greatly affected the quality and construction time of the components.
3D Printing: As long as the model is uploaded and the orientation, layer thickness and support position are selected, most of AM machines can print complete parts.
FAQ:
CNC machining is a subtractive process that removes material from a solid block, while 3D printing is an additive process that builds parts layer by layer from nothing.
CNC machining works with metals, hardwoods, softwoods, thermoplastics, acrylics, modeling foams, and waxes—each requiring different cutting tools.
3D printing is compatible with metals, ceramics, waxes, sand, and composite materials, depending on the specific technology used.
CNC machining generally cuts faster, but it requires more setup and planning. 3D printing is slower overall but can form parts in one step without multiple repositioning.
CNC machining typically offers better precision and surface quality, especially for small features, due to the sharpness and geometry of the cutting tools.
It depends on the technology:
FDM printing layer thickness: 100–200 microns
Material jet printers: as fine as 16 microns
Resolution also depends on the material delivery method or laser/light spot size.
CNC machining provides a smoother and higher-quality surface finish than most 3D printing processes.
Yes, especially with SLS (Selective Laser Sintering) and SLM (Selective Laser Melting), 3D printing can support batch manufacturing.
CNC requires careful planning including:
Tool selection
Spindle speed
Cutting angles
Toolpath and entry points
These factors directly affect the outcome of the part.
3D printing setup is relatively simple:
Upload the digital model
Choose orientation, layer thickness, and support structures
Start the build
Most machines automate the rest of the process.
