3D printing has taken the world by storm and it is incredibly becoming the most favourite industrial processes of today. From the simple design that would take engineers weeks to complete before and just a few hours through rapid prototyping, there is no doubt that why this technology has swept businessmen off their feet. But the question is how does 3D printing really works?
In general, there are only a few types of additive manufacturing technology. However, there are various kinds of these types, each having a distinct quality. Even older technologies have their own strengths and flaws, just like extrusion deposition. These types are more likely to find a long term place in the market through sheer simplicity and lack of expense.
The one which is considered as the father of all 3D printing technologies is stereolithography (SLA). This is a layer-based system which makes use of a laser to solidify portions of a liquid medium known as photopolymer. A metal platform is wrapped up in the photopolymer which holds one layer’s-thickness away from the surface. This usually comes in more or less a 10th of a millimetre. Then, an ultraviolet laser traces out the first layer’s shape which would produce a hardened solid wherever it touches, and then the platform descends another layer’s-thickness. A thin film of photopolymer sweeps in the cover the growing object, and the laser hardens the next layer atop it. Although this is not considered as the most effective way of printing, it can still use some very interesting building materials, like ceramics, for a relatively low price.
But the real beginning of the sudden storm came a bit later when the simplest way of 3D printing came in the mass market, the extrusion deposition. This is a process where a robot nozzle moves about, squeezing out a plastic building material like a very, very precisely controlled hot glue gun. Some plastics are meant to harden as they cool in the air, others are mixed with a hardening agent as they’re laid down, but in any case the goal is to create one hardened layer on top of another. If the layers are thin enough, and laid down precisely enough, this can create surfaces that seem fairly smooth, like a traditionally molded plastic object.
In simple words, all 3D printers on the market today are, at least primarily, additive. We can say that the work is done by precisely depositing more and more of a building material and in the end producing an object out of nothing. This is contrasting to the process of sculpture, in which you shave an existing object down. Today, there are 3D printers that can do carving on top of a recently created object, but sculpture will never be able to do the advantages that additive manufacturing brings.