Difference between additive manufacturing and cnc

 

Difference	Additive Manufacturing	CNC
1. Complexity	more complex parts and undercuts, internal features can be easily built in a single part.	certain parts cannot be fabricated by CNC unless they are broken up into components and ressemble at a later stage.
2. Material	originally developed for polymers, waxes and papers laminates subsequently composites, materials and ceramics.	can work with a wide range of materials, including high density metals, wood, wax, plastics but generally used for hard metals.
3. Speed	parts produced in a single stage (in few hours)	requires considerable setup and process planning particularly as parts become more complex, made in multistage (may take weeks).
4. Geometry	Undercuts, enclosure, sharp corners. {convert 3D problem into 2D problem}	CNC: cylinders, cuboids, cones.
5. Programming	The worst thing is that the path will not be built very well if the programming is not done properly.	incorrect programming of a CNC machine could result in severe damage to the machine and may even be a safety risk.
6. Accuracy	more accurate	comparatively less
7. Process	additive process	subtractive process.