3D printing which also known as prototyping is a new type of manufacturing technology that stacks materials layer by layer to build a solid. Although there are many different 3D printing technologies on the market, no matter whether the final part is a rapid prototype or a functional part, the general 3D printing principle is basically the same and will not change.
From the initial CAD design to 3D printed parts, 3D printing follows a series of common processes.
1. Design of modeling software
It is the first step to convert into a digital model in the whole process of 3D printing. The most common way to transform into a digital model is to use computer-aided design software (CAD). There are many free and professional CAD programs that are compatible with 3D printing. Reverse engineering can also be used to convert 3D scans into digital models.
2. STL file conversion and operation
Unlike traditional manufacturing methods, the key point in the whole process of 3D printing is to convert digital model files into STL (stereolithography) files. STL uses triangles (polygons) to describe the three-dimensional parameter information of the object. Before converting the model to an STL file, several model limitations should be considered, including physical size, water tightness and the number of polygons.
If it is converted into an STL file, the file will be exported to the slicing software for processing. This program converts STL files into Gcode. Gcode is a type of numerical control programming language. It is used in computer-aided manufacturing to manipulate automated machine tools (including CNC machine tools and 3D printers). The slicer program also allows designers to customize the construction parameters, including support, layer height and part orientation.
3. 3D printing process
3D printers generally consist of many small and complex parts, so correct maintenance and calibration are particularly important for producing accurate prints. In this part, printing materials are also loaded into the 3D printer. The raw materials used in 3D printing generally have a shelf life and need to be handled carefully. Although we can recycle excess 3D printing materials in some processes, if they are not regularly replaced, repeated use will result in reduced material performance (for example, drawing due to moisture).
If you start printing, there is no need to monitor the operation of the 3D printer. The 3D printer will follow an automated process, and generally will only give an alarm when the machine runs out of materials or the software has problems.
4. Remove 3D printing support
For some 3D printing technologies, removing the 3D printing model support is as simple as taking the printed model directly from the printing platform. For other more industrialized 3D printing methods, removing the support is a special workflow that involves accurately obtaining the printed model objects, and still encapsulating them in construction materials or adhering to the 3D printing platform. This type of method requires complex disassembly procedures, skilled machine operators, safety equipment and a controlled environment.
5. Processes after 3D printing
The post-processing procedure depending on the 3D printer technology, different technologies have different procedure.SLA 3D printing technology requires curing under ultraviolet light before model processing. Metal parts usually need to be stress-relieved in an oven, while parts made by FDM technology can be directly processed manually. Most 3D printed models can be polished, and other post-processing techniques (including high-pressure air cleaning, polishing, and coloring) can be used to prepare the final 3D printed model.