In it’s simplest definition, 3D printing, or additive manufacturing as it’s also known, is the process of making three-dimensional solid objects from digital designs.
There are a couple of “stages” to 3D printing, with the first stage being to lay out an original idea with digital modelling — that is, with computer aided design (CAD), purchased templates or animation modelling software.
Whichever program you choose, you’re able to create a virtual blueprint of the object you want to print. The software program then divides the object into digital cross-sections so the printer is able to build it layer by layer. The cross-sections essentially act as guides for the printer, so that the object is the exact size and shape you want. If you don’t wish to design the product yourself, there still many options available such as sourcing existing templates or models, submitting your idea to a 3d design service and so on.
Once you have a completed design, you send it to the 3D printer with the standard file extension .STL (for “stereo lithography” or “Standard Tessellation Language”). STL files contain three-dimensional polygons that are sliced up so the printer can easily digest its information.
The 3D Printing Process
3D printing is characterized as “additive” manufacturing, which means that a solid, three-dimensional object is constructed by adding material in layers. This is in contrast to regular “subtractive” manufacturing, through which an object is constructed by cutting (or “machining”) raw material into a desired shape.
After the finished design file is sent to the 3D printer, you choose a specific material. This, depending on the printer, can be rubber, plastics, paper, polyurethane-like materials, metals and more.
Printer processes vary, but the material is usually sprayed, squeezed or otherwise transferred from the printer onto a platform. When the printer is told to print something, it pulls the bioplastic filament through a tube and into an extruder, which heats it up and deposits it through a small hole and onto the build plate.
Then, a 3D printer makes passes (much like an inkjet printer) over the platform, depositing layer on top of layer of material to create the finished product (look closely — you can see the layers). This can take several hours or days depending on the size and complexity of the object. The average 3D-printed layer is approximately 100 microns (or micrometres), which is equivalent to 0.1 millimetres. Some printers, like the Objet Connex, can even deposit layers as thin as 16 microns.
Throughout the process, the different layers are automatically fused to create a single three-dimensional object in a dots per inch (DPI) resolution. SOURCE: Mashable