As a result of technological prowess, 3D printing is increasingly in demand by individuals and professionals. Although it is not a new technique, it is today that 3D printing becomes important because it is now very useful or even essential in certain fields. What is 3D printing? How does a 3D printer work? What is the principle of additive manufacturing? You will have the answer to all your concerns in this guide.
What is 3D printing?
Unlike other techniques such as milling or grinding, 3D printing is based on additive manufacturing. That is to say by adding material layer by layer. Indeed, 3D printing makes it possible to carry out digital materialization in three dimensions (along the X, Y and Z axis) thanks to a 3D scanner. This printing technology is very useful in the world of design or engineering.
Individuals can buy a 3D printer for under $100 and test it out at home. There are also online 3d printing services in Austin that allow you to send a model to be printed in larger or smaller series.
How does a 3D printer work?
To function, the 3D printer needs several elements offering various roles.
- The consumable: it can be a filament, a resin or a powder.
- The 3D model file: this can be in STL or OBJ format
- The slicer: it will serve as a guide to the printer using a G-code file
In addition, we also need a computer first and foremost. To perform a 3D print, the model must first be sent to the printer. This first operation will allow the latter to identify the object to materialize. Then, the slicer is requested during the second stage. It will be necessary to insert the filament there to proceed with its heating on the printing plate and its cutting into fine particles. The particles produced are then superimposed to be printed.
What is the principle of additive manufacturing (AM)?
The principle of additive manufacturing is very simple. We must point out that the process of additive manufacturing is just the opposition of subtractive manufacturing. The latter makes it possible to design an object from another by removing unnecessary parts. This process is very well illustrated in machining and carpentry where with wood or metal it is designed furniture or metal parts. While additive manufacturing leads to a design by adding materials layer by layer.
3D printers are very convenient and time saving for rapid prototyping and efficient production. They also optimize the raw material and allow less waste than with traditional machines. This is due to the adopted process which is additive manufacturing. This process works in such a way that the materialization takes place through the superposition of small particles. As needs grow, several 3D printing techniques have been created. But they all do not have the same precision and the same cost. It is therefore necessary to adapt the printing techniques according to our expectations.
The different 3D printing techniques?
The strategies adopted at the level of 3D printers are varied. Among them, three stand out. It is :
- Deposition of molten material or FDM (Fused Deposition Modeling) with a filament
- Light curing with resin
- Laser sintering or fusion with powder.
- Each of them is underpinned by specific processes while offering various advantages.
Melt deposit (filament)
The melt deposition technique is the best known of all. This technique also called FDM, FFF (Fused Filament Fabrication), or MDP (Molten Polymer Deposition) was created in 1988 and is still relevant today.
A 3D printer with FDM technology consists of several elements:
- A mass memory (USB key or memory card): This medium will contain the G-CODEs for guiding the slicer.
- A set of electronic components: it controls the motors of the machine.
- Three motors: to allow movement of the print head and platen. The print bed moves along the Y axis while the print head moves along the other two axes X and Z.
- A print head: it is equipped with a motor, a heating resistor, a fan and a nozzle.
- A spool of filament
- A frame: also called a chassis, it serves to hold all the equipment.
- FDM 3D printers are used with filament. Copper, flexible TPUs, PETG, nylon, PLA, ABS and bronze are all available filament materials. Also, these filaments are of various diameters and colors.
Light curing (Resin):
Printers that use this technology are beginning to be adopted by the public even if they remain more expensive than those with the deposition of fused material. It is certainly because the resin is more expensive than the filament spool and their precision is not comparable. That of resin printers is much higher than that of FDM printers. Resin printers come in three forms depending on the curing tool. This can be a UV laser, a UV projection lamp or a UV light screen.
Regarding its different parts, the resin printer has in common with the FDM printer a mass memory, a chassis, an electronic card and a tray. The elements that mark the difference are the printing screen and the resin tank. The tank can collect resin of different versions.
Laser sintering or melting (Powder):
The consumable involved in this printing technique is the powder. It should be understood that in 3D printing the precision depends on the cost of the printer and the consumable. In addition, the consumable exists in various forms (metallic, ceramic, thermoplastic). Powder 3D printers are more precise than others and therefore are expensive. In addition, the consumable exists in several forms (metallic, ceramic, thermoplastic).
Powder 3D printers also have several elements in common with other printers. The main elements that stand out from the rest are the print tray, the laser and the reflection lens. The print tray is used to hold powder where the object will be dipped. The reflection lens intervenes when it is necessary to direct the laser to give shapes to the layers of the object. The laser, on the other hand, melts the consumable.
The state of the surface during the final rendering differs according to the role of the laser. When it comes to SLS (Selective Laser Sintering), to mean selective laser sintering, the surface of the print has grains. On the other hand, SLM (Selective Laser Melting) resulting in selective laser melting makes it possible to have smoother surfaces.
