CNC machining is a fairly common part production technique that can be used to produce highly accurate and detailed parts; 3D printing is a technique that uses digital technology to convert design drawing data from a 3D model into the solid of an object and can be used to create parts for a variety of complex structures.While both processes are standard today, each is constantly evolving to meet different needs – so it is important to understand which method is best suited to your needs.
We have prepared an exhaustive comparison of CNC and 3d printing, you can go through these details to compare the two methods and decide which one to use.
Overview of CNC machining
CNC (Computer Numerical Control) machining is a manufacturing process in which pre-programmed computer software dictates the movement of factory tools and machinery. The process can be used to control a range of complex machinery, from grinders and lathes to mills and routers.
With CNC machining, three-dimensional cutting tasks can be accomplished in a single set of prompts. It is mostly used for creating complex parts with high precision and repeatability.
Common types of CNC machines
1. Lathe: A lathe machine is used for machining metal parts from a rotating workpiece. It is used to shape metal into different shapes, sizes and contours.
2. Milling Machine: A milling machine is used for cutting or shaping metal and other materials. It can be used to create slots, holes, grooves, contours and surfaces.
3. Router: A router is used to cut, shape, and finish wood and other materials. It is used to create intricate patterns and shapes in wood, plastic and other materials.
4. Plasma Cutter: A plasma cutter is used to cut metal and other materials using a plasma torch.
5.Waterjet Cutter: A waterjet cutter is used to cut metal and other materials using a high-pressure stream of water.
Overview of 3D printing
3D printing is a process of using computer-aided design (CAD) to create three-dimensional physical objects from a digital model. It is a form of additive manufacturing, where an object is created by adding successive layers of material.
3D printing is used in a variety of industries, from automotive and aerospace to medical and consumer electronics. It is also used to create custom-made parts, prototypes, and production parts. 3D printing can be used to create a wide range of products, from jewelry to toys to medical devices.
The difference between CNC machining and 3d printing
Comparison of working principles
The most notable difference between 3D printing and CNC machining is the way the object is created.
CNC machining：a subtractive process is used, where a block of material is cut away to create the desired shape.
3D printing：3D printing uses an additive process, where a 3D model is broken down into thin layers and then each layer is printed one at a time.
Comparison of materials
CNC machining: CNC machining can be done with a wide range of materials such as metal alloys, plastics, waxes, wood materials etc. CNC machining allows for fast and precise machining of other materials.The metal commonly used in CNC machining is aluminium.
3D printing: ABS (plastic), PLA (eco-friendly plastic), resins, glass fibre reinforced plastics, metal powders, graphene, etc.It is important to note that these materials should not be used with high melting point metals.
CNC machining is generally more precise than 3D printing. CNC machining is capable of producing parts with a tolerance of up to +/- 0.005mm, while 3D printing typically has a tolerance of +/- 0.1mm.
Additionally, CNC machining produces smoother surfaces than 3D printing, which can be beneficial for certain applications. CNC machining also has the advantage of being able to produce parts with complex geometries, while 3D printing is limited by the complexity of the object that can be printed.
It really depends on the part design, materials etc. Parts with complex internal structures are almost impossible to CNC-mill. However, anything that looks “a bit like an ashtray” and can be easily clamped for milling is often faster, easier and more accurate to produce on a CNC milling machine than on a 3D printer.
For big size project with exquisite surface treatment requirement.
It is cheaper with CNC machining but have to bearing the disadvantage of piecemeal gluing risks of weaken of strength.
Will metal 3D printing replace CNC machines in the near future?
I think metal 3D printing is a rapidly evolving technology, but it is unlikely to completely replace CNC machines in the near future.
A long time has passed since the production of laboratory prototype parts to full production manufacturing. But to replace CNC, I see 3D as a complement to CNC.The great advantage of 3D printing lies not in its speed (for now), but in the ability to design and manufacture items that cannot be made any other way. When it comes to mass production of metal parts, cnc machining is superior, both in terms of material and speed.