What is 3D Printing?

3D printing is a method of manufacturing everything from tools to shoes to jewelery, or even car and aerospace parts using a computer-controlled printer. The fundamental rule of 3D printing is that it’s an additive manufacturing technique, unlike machining, turning, milling, and sawing which are subtractive.

While there are different kinds of 3D printing, all 3D objects are generally built out of layers. A 3D printer starts with the bottom layer, waits for it to dry or solidify, and then works its way up. This layering process differs depending on the printer and the material it works with — metal, plaster, polymer, resin — but it also depends on whether it’s an industrial or commercial 3D printer.

Industrial vs. commercial

While consumer- and small business-oriented 3D printing is only just taking off, mostly thanks to the MakerBot and RepRaps, 3D printing has been used in an industrial setting for 30 years. Industrial 3D printers tend to be very large and very expensive, but at the same time they are a lot faster than commercial printers. Some industrial printers can print with multiple nozzles at the same time, or even use metal (more on that later). For the most part, industrial printers are nearly always used for rapid prototyping (usually by architects, automakers), but sometimes 3D printed objects — especially in the case of metal objects — are used in final products.

Consumer-oriented 3D printers are cheaper, smaller, slower, and are usually lower resolution than their industrial counterparts. Consumer printers are still used for rapid prototyping, but they’re also used by people who just like the idea of printing stuff out. Generally, consumer printers use thermoplastic extrusion — i.e. it dribbles out tiny dots of melted plastic.

Different printing techniques

Depending on the material used, how many colors you want, the resolution you require, and how much money you’re willing to fork out, there are at least five popular 3D printing methods to choose from. Some are very similar, but some are really rather crazy (or brilliant).

• Fused deposition modeling – The most common 3D printing method is fused deposition modeling (FDM). The raw material with this process is a spool of plastic or metal wire, which is melted and placed by the printer’s nozzle. It quickly hardens, and then the next layer can be added. As far as commercial printers are concerned (like the MakerBot), FDM always uses plastic wire (filament) and is usually called “thermoplastic deposition” in layman’s terms
• Inkjet printing — Using special inks (resins and binders) it’s possible to build up a 3D model using a device that’s very similar to a home or office inkjet printer. Layer upon layer of resin and binder are added until an object is created. This is the only 3D printing process that allows for custom colors.
• Selective laser sintering – Sintering is the process of creating solid objects from powders, and in the case of selective laser sintering (SLS) the powder can be metal, plastic, ceramic, or glass. Basically, SLS uses a pulsed laser to “draw” the desired cross-section. The powder fuses, and then then the laser forms the next layer on top. This is very much an industrial method, as it requires a rather strong laser.
• Digital light processing – With DLP (yes, the same technology behind DLP projectors), a vat of liquid polymer is turned into a very strong solid by exposing it to light. Very high accuracy/resolution can be achieved with this technique — and again, this is an industrial method. Stereolithography is similar to DLP manufacturing, but a lot more expensive.
• The others – Finally, there are a few 3D printing techniques that aren’t used extensively, but could be in the future. Resin can be cured using LEDs (similar to the DLP approach); 2-photon photopolymerization can be used to create ultra-small 3D-printed features; laminated object manufacturing uses bits of paper or card stuck together that are then cut out using a laser.

The future of 3D printing

Arthur C Clarke stated that; "Any sufficiently advanced technology is indistinguishable from magic." "Profiles of The Future", 1961 (Clarke's third law)

Beyond 3D printing is mystical technologies that may seem far fetched but rest assured that they are based in real, proven technology. Everyone knows about the Star Trek teleporter. Its a magical technology that wisks someone away to a new location without travel. It was great for TV on Star Trek when Captain Kirk and the crew needed to move to a new location quickly for the show's 1-hour timeframe.

How far fetched is teleportation?Actually...its real and we've already done it! Presently, the record distance for quantum teleportation is 143 km (89 mi) with photons (Light), and 21m with material systems (atoms). On September 11th, 2013, the "Furusawa group at the University of Tokyo has succeeded in demonstrating complete quantum teleportation of photonic quantum bits by a hybrid technique for the first time worldwide. Yes, matter has been moved between points without actually traveling between points. Scary stuff but you might receive your orders from Amazon this way in the year 2200.

Far more likely though is a more practical technology called Molecular manufacturing. Think of it like working with Legos where the legos are atoms or molecules of a material. The product you want is assembled using tiny bits of material until the product is formed from basic elements much like inkjet printers make colors from just a afew basic colors. After all, everything in the universe is made of just 3 things: Protons, Nuetrons and Electrons. Watch the video and you'll see a machine making machines from this very obtainable technology. It could be real in as few as 25-50 years!

We’ve already alluded to a few uses for 3D printing — prototyping, making stuff at home — but it’s worth diving into some of the crazier things that 3D printing is capable of now, and what it will be capable of in the future.

3D printers can be used to create titanium aircraft parts, human bones, complex, nano-scale machines, and more. In the future, it’s fairly safe to assume that we’ll be able to manufacture almost anything with a 3D printer — and everything we can’t make with a printer (clothes, textiles), automated CNC machines, or something like them, will take care of. Ultimately, 3D printers might also be the key to matter replicators, just like in Star Trek. It’s important to note that we already have very accurate tools for creating 3D models of existing objects; we have the ability to scan a cup, and then create an exact copy using a 3D printer.

Eventually, one day, you will walk up to a 3D printer and say “make me an iPad,” and it will make you an iPad. If we can create 3D printers with atomic-level resolution, they might also usher in another Star Trek gadget: teleporters. There’s also the (rather worrying?) fact that many commercial printers are labeled as “self-replicating,” in that they’re capable of printing their own replacement parts. In other words, if we gave a 3D printer some kind of artificial intelligence, who knows what it would into.

[via ExtremeTech]