Introduction to 3D printing
The rise of 3D printing
3D printing is a method of creating three-dimensional objects, typically made of plastic, by adding multiple layers on top of each other. The object’s design is created on a 3D modelling software and then printed using specialised machines called 3D printers. These printers melt and deposit plastic filament layer by layer, building the part from the bottom up.
While the technology was first used in the 1980s, it became more popular and accessible to hobbyists around 2005. Since then, there have been numerous 3D printer suppliers, new materials with various properties, open source management software solutions, and a large community of people supporting and developing the technology.
Initially, 3D printers were mainly used for artistic projects such as figurines or souvenirs. However, buyers soon realised the potential for more practical parts that could replace damaged components or expand the possibilities of finished products. A vivid example of this is the numerous improvements that buyers make to their 3D printers, such as dust covers, holders, and electronic boxes.
There are three main reasons why 3D printing is currently unbeatable in the production of small batch plastic parts: freedom of design, production speed, and low cost.
Unlike conventional machining technologies that rely on material removal, 3D printing is an additive process. Here are some of its advantages:
- During the printing process, the machine has access to every point of the model – it is possible to create a hollow, fully enclosed spherical part with specific shapes on the inside;
- Some printers can include two or more different materials in the same part – that can be used for multicoloured designs or if special mechanical properties are required;
- The geometrical complexity does not affect the print – all the necessary information is in the 3D model; since the printer builds the part layer by layer, every complex shape is just a combination of simpler 2D polygons;
- Various printing parameters can be modified within the printer management software. Changing the part density or layer thickness, for example, can make the final product dense and strong or almost hollow and hence lighter and cheaper.
Saves time and money
Once a 3D model is complete, the only operation left is the printing itself. The lack of additional steps saves lots of time and effort, especially when an unexpected design alteration is required and the part has to be remade. The printing usually takes only a couple of hours (depending on its size) and no operator or subsequent processing are needed. The process is relatively inexpensive (low cost of materials and tools compared to traditional machining) and easily automated. For example, on our website you can upload an .STL model and immediately see the price and delivery time. This significantly reduces the overall ordering time as well as the possibility for human error.
Applications of 3D printing
With the development of new plastic materials and advanced printers, 3D printed parts are becoming a reliable alternative to some metal parts used in various industries. The technology is not an one-size-fits-all solution but great results can be accomplished if the following conditions are met:
- The parts are subjected to light to moderate loads; even though there are multiple engineering grade plastics (PETG, ABS, Nylon) their strength can’t compare with the strength of metals;
- The parts are loaded in no more than two perpendicular directions and the printing orientation is chosen appropriately – because of the way 3D printed parts are made they are weaker in the vertical direction (where layers are added on top of each other); loading and printing orientation are important factors during the design process;
- The parts are not subjected to high temperatures – most plastics lose their mechanical properties at about 70 degrees Celsius;
- The number of printed parts is relatively small; with orders larger than 10 000 units, other technologies, such as injection moulding, become more cost-effective.
The 3D printing technology is not a replacement for the standard CNC machines, but rather a complementary tool that can bring significant reductions in both manufacturing time and cost for specific parts. There are many opportunities for optimization in the CNC machining workshop, as many of the parts and tools there meet the criteria mentioned above.
In the upcoming articles we will present some curious use cases of 3D printed parts within the machine building industry. Stay tuned!
What is your experience with 3D printing! Or maybe you have a question? Tell us in the comment section!