3D printing or additive manufacturing is a process of making three dimensional solid objects from a digital file.
The creation of a 3D printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the object is created. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object.

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How does 3D printing work?
It all starts with making a virtual design of the object you want to create. This virtual design is for instance a CAD (Computer Aided Design) file. This CAD file is created using a 3D modeling application or with a 3D scanner (to copy an existing object). A 3D scanner can make a 3D digital copy of an object.

3D scanners
3D scanners use different technologies to generate a 3D model. Examples are: time-of-flight, structured / modulated light, volumetric scanning and many more.

Recently, companies like Microsoft and Google enabled their hardware to perform 3D scanning, for example Microsoft’s Kinect. In the near future digitising real objects into 3D models will become as easy as taking a picture. Future versions of smartphones will probably have integrated 3D scanners.
Currently, prices of 3D scanners range from expensive professional industrial devices to $30 DIY scanners anyone can make at home

3D modeling software

3D modeling software also comes in many forms. There’s industrial grade software that costs thousands a year per license, but also free open source software, like Blender, for instance. You can find some beginner video tutorials on our Blender tutorials page.

When you are a beginner and the amount of choices are a bit overwhelming, we recommend to start with Tinkercad. Tinkercad has a free version and it works in browsers that support WebGL, for instance Google Chrome. They offer beginner lessons and has a built in option to get your object printed via various 3D printing services.

When you have a 3D model, the next step is to prepare it in order to make it 3D printable.

From 3D model to 3D printer
You will have to prepare a 3D model before it is ready to be 3D printed. This is what they call slicing. Slicing is dividing a 3D model into hundreds or thousands of horizontal layers and needs to be done with software.
Sometimes a 3D model can be sliced from within a 3D modeling software application. It is also possible that you are forced to use a certain slicing tool for a certain 3D printer.
When the 3D model is sliced, you are ready to feed it to your 3D printer. This can be done via USB, SD or wifi. It really depends on what brand and type 3D Printer you have.
When a file is uploaded in a 3D printer, the object is ready to be 3D printed layer by layer. The 3D printer reads every slice (2D image) and creates a three dimensional object.

Getting started with 3D Printing

Getting started with 3D printing means asking yourself what you would like to learn first. Are you interested in the hardware, or do you want to focus on creating objects.
We’ve created a 3D printers for beginners buyers guide to help you decide if you should choose a pre-assembled 3D Printer or a 3D printer kit.
In case you have a tight budget and you want to start your journey into learning 3D printing, cheap 3D printer kits can be a great starting point. If you are interested in going this route, please read our article about cheap 3D printer kits. This article explains what to look for when you’re comparing these kits.

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