Additive manufacturing is considered to be the next industrial revolution. However, subtractive manufacturing still continues to hold strong in the modern era and dominates major production and assembly lines such as automobiles, FMCG, electronics and many more. But which manufacturing technology is superior and would see the light of the future. Read the comparison between additive manufacturing and subtractive manufacturing and know how both the processes differ.
Additive manufacturing technology is capable of producing much complex designs and models within a limited time-frame. The reason for the superiority is simple- the additive technology works by building layer-on-layer which is few 1000th of an inch at a time. Imagine building a complex prototype having thousands of detailed cross sections where each layer has a different intricate design and geometrical dimensions. The 3D printing technology is so subtle and intricate in its 3D model construction that the detailed layers are placed over one another in a precise manner. The 3D printer can build the open and hollow part of the prototype simultaneously without any difficulty. The result is you get a highly detailed three-dimensional model which has high tolerances inside and outside. The 3D printing process is automated with no human input except the creation of CAD model which is uploaded to the 3D printer.
In contrast, subtractive manufacturing works by removing materials from a bigger source. The limits of cutting and drilling technology severely restrict the creation of hollow parts from a single piece. The limits of technology also restrict to the number of details that can be created with a single tool. Despite these technical limitations, it does not mean the parts produced by subtractive manufacturing are not precise. Given enough time, the CNC machine operator can create complex parts with precision using varied tooling methods.
The choice of material greatly depends on the applications of the prototype. The materials used in 3D printing vary from Nylon, Resin, ABS, Stainless Steel to Gold & Silver, Gypsum, Ceramic, and Titanium. Subtractive manufacturing which heavily depends on the use of CNC machine works with materials like metal, wood, foam and any other material that can be successively cut by a CNC machine.
If you need a single prototype or a few for short runs, additive manufacturing is the way to go. Additive manufacturing is right for a small batch of prototypes with less lead time as there is no special setup needed to accept right base material. On the other hand, subtractive manufacturing requires a great deal of setup even to produce a single prototype. The operator needs to program the CNC tooling path that needs a lot of time and effort in comparison to the automated process of 3D printing.
However, subtractive manufacturing is ideal for large production volumes and the process becomes more cost-effective. 3D printing technology has advanced in recent years and today you can find 3D printers with new capabilities which can build up to two models simultaneously. In simple words, 3D printing technology is unsuitable where large volumes of a product need to be manufactured in lesser time at lower cost.
In sum, both the types of manufacturing processes, i.e. additive manufacturing, also known as 3D printing and subtractive manufacturing are effective especially during certain phases of the production of prototypes. As of today, companies, in order to gain the best out of both the technologies, are combining both these technologies and using the one that best meets the needs of the production phase and the part that is being manufactured.