How does the 3D printer work?

In addition to liquid plastic, powder made of metal or ceramics is used in industry as a material for 3D objects to be created. Even sand can be processed into 3D workpieces. After all, old and valuable glass is also made of molten sand.


Unlike toner powder, the powder is melted here and then baked together to form the corresponding shapes. Baking together is the so-called additive manufacturing process.


There are now several processes for producing a 3D object. For home use, 3D printers that work according to the so-called fused deposition modeling (FDM) process are of particular interest.

In FDM, the material is heated to a high temperature and liquefied so that it can be injected in this state through a so-called extruder onto a working platform. The materials are applied in very thin layers. They are cured layer by layer by means of a laser beam. The working platform is lowered bit by bit while the laser continues to work at the same height.


This is how, for example, spare parts, chess or other game pieces, model cars, dolls or other toys are created. There are virtually no limits to imagination and creativity.


Additive manufacturing thus gradually gives the figure to be created its shape. The technology behind this is either stereolithography (SLA) or selective laser sintering (SLS), there is also direct metal printing (DMP) and intensive research is already being carried out into others.

Extruder - the printer cartridge for the 3D printer.

The material is heated in the extruder. This enormously important component of any 3D printer heats plastics, metal powder or sand to the desired working temperature. Once liquefaction has taken place, the further process is roughly similar to that of a printer cartridge in that the extruder sprays the now liquefied material through fine nozzles onto the working platform, thus printing the object.


Another thing an inkjet printer and a 3D printer have in common is their design. Just as an inkjet printer has a single or multiple cartridge, a 3D printer also has multiple and single extruders, with a dual extruder or a single extruder often being used. For simple home use, the single variant is standard.


The quality of an extruder is characterized, among other things, by the degree of uniformity with which it injects the material onto the work surface. After all, the more uniform this process is, the cleaner the 3D print will be. Also of interest is how fine the material can be in order to pass through the nozzle.

Filament: the ink for the 3D printer

Filaments in the 3D printer are the counterpart for the ink in the classic inkjet printer. For 3D printing or the FDM process, thermoplastics such as PLA, ABS and others are mostly used.


ABS stands for acrylonitrile-butadiene-styrene and belongs to the amorphous thermoplastics. Lego® building blocks, for example, are made from this material.


As a filament, the material is more heat-resistant and stable than PAL, as it only softens above 100 degrees Celsius. However, this material is again more difficult to process because it shrinks considerably when it cools down. The worktop must be heated so that the first layers do not already contract after application, causing the whole piece to warp unevenly. ABS is therefore rather unsuitable for laymen.


With PAL (polylactide) filament, on the other hand, good results can be achieved even by non-professionals. The melting and thus the processing temperature are lower than that of an ABS material, and subsequent processing is also more likely to succeed if the printed product is made of PLA. Furthermore, PLA has the advantage that it does not shrink so much after cooling. However, since the material already softens at 60 degrees Celsius, you should not leave workpieces made with it in your car at the height of summer, unless you like sculptures modeled on Dalí.

In the industrial sense, PLA o - also called polyester of lactic acid - is even biodegradable under special conditions, but not manageable for the domestic compost heap.


In a store for 3D printing, the filament is offered to you wound around a spool, so that it resembles a very thin wire. The finer the material, the finer the end product can be processed. Thus, you can find thicknesses of more than 200 mm, but also 175 mm or 100 mm and less on the market and in industrial production.


Suppliers are, for example, German Reprap from Feldkirchen, EnvisionTEC from Marl, 3D Systems, FormLabs, MakerBot / Stratasys from the USA or Ultimaker from the Netherlands. Even the electronics company Conrad offers its first own 3D printer, the Renkforce RF1000. The work platform lowers itself piece by piece. This is how, for example, spare parts, chess or other game pieces, model cars, dolls or other toys are created. There are virtually no limits to imagination and creativity.

Who benefits from the use of a 3D printer?

The hotelier and restaurant owner could use pasta from the 3D printer to offer his very own individual pasta speciality, while the confectioner could design his special chocolate creations on the computer and print them out to individual customer specifications. In these cases, of course, the ink would be made from food. People are already working on such an "individual pasta machine." However, printing the noodles would still take hours - too long for the hungry guest.


The architect could be happy about an easier production of his models in the printer, instead of having to do it himself in time-consuming work and losing precious time. Artists, too, could let off steam and entrust their creativity to the 3D printer. Archaeologists and museologists would be grateful if they could quickly produce a faithful replica of the valuable finds and present them to the public in exhibitions. In this way, the original can be better protected and preserved.

The 3D printer for home use

Printing out spare parts quickly yourself, for example replacing small lost game pieces or broken towel hooks, also makes the 3D printer attractive for home use. Likewise, cases or housings for small technical devices such as the smartphone or tablet can be printed quickly, conveniently and accurately. Even dolls or model cars as toys for the little ones make the 3D printer at home a sensible purchase.


If you have time, you can also get creative at home and design and print jewelry and fashion accessories yourself, even without having a steady hand. Maybe you just need a small gift? Then print one for yourself! A self-created egg cup for Easter, Christmas tree ornaments for the holy season or fashion jewelry for the cradle celebration can all be designed and given away yourself. On forwarding expenses, exchange stress with Nichtgefallen or delivery waiting period can be renounced. The possibilities are almost limitless.

Models for the 3D printer

In addition to certain software that allows you to make your own creations and work on ideas yourself, there are already 3D printing studios that offer good quality. Especially fascinating there is the possibility to have a model made of yourself. To do this, you have yourself photographed from all sides and the corresponding software makes you appear in miniature from the 3D printer.


Of course, there are already websites that offer models for 3D printing if your own creativity is not too far off or you need some inspiration. Downloading such models is still quite expensive But once the demand increases, the supply will also increase. Prices should then also adjust, because competition not only stimulates business, it also increases customer friendliness. The costs for the user should fall.

A 3D printer with a 3D scanner is also an interesting development. Such a device is already on the market. Since 2015, for example, the manufacturer xyzPrinting from Taiwan has been offering the combo with its Da Vinci 1.0 AiO. This allows you to scan in your objects via 3D scanning, edit and save them with the appropriate software, and then have your version of the object printed out again. The Da Vinci is available on the market for around 1000 euros. However, when making your purchase, consider the consumables, the filaments, which, like the equipment, are currently still luxury items.


The home 3D printer may still be too expensive and the effort from the idea of a workpiece to the result and implementation too great, but development is proceeding at breakneck speed, especially since the invention is not brand new. The novelties in the near future will be the affordability of 3D printers and their work material, be it PLA, ABS, liquefied wood, metal powder or other filaments. Internet sites for models will abound, so downloading models will also be affordable.

The "ink" for the 3D printer

Mostly thermoplastics are used, such as polyactide (PLA) or acrylonitrile butadiene styrene (ABS). However, PLA has the advantage that it does not shrink as much after cooling. However, since it already softens at 60 degrees Celsius, you shouldn't leave workpieces made with it in your car at the height of summer, unless you like sculptures along the lines of Dalí. In the industrial sense, PLA - also called polyester of lactic acid - is even biodegradable under special conditions, but it is not manageable for the domestic compost heap. ABS is more heat-resistant and stable, as it only softens above 100 degrees Celsius. However, this material is again more difficult to process, as it shrinks considerably when cooled. The worktop must be heated so that the first layers do not already contract after application, causing the whole piece to warp unevenly. By the way, the famous Lego bricks are made of this plastic.


In addition to liquid plastics, metal powders or ceramic powders are also used in industry to produce prototypes. Even sand can be melted as "ink", cast and processed into workpieces. After all, the ancient and valuable glass is also made of molten sand.


How do you get models for the 3D printer?

In addition to certain software that allows you to make your own creations and work on ideas yourself, there are already 3D printing studios that offer good quality. Especially fascinating there is the possibility to have a model made of yourself. To do this, you have yourself photographed from all sides and the corresponding software makes you appear in miniature from the 3D printer.


Of course, there are also already websites that offer models for 3D printing if your own creativity is not too far off. In addition, you can also get ideas there. Downloading such models is still quite expensive, but once the demand increases, there will also be a broader offer. Prices should then also adjust, because competition not only stimulates business, it also increases customer friendliness. The costs for the user should drop.


The home 3D printer may still be too expensive and the effort from the idea of a workpiece to the result and implementation too great, but development is proceeding at breakneck speed, especially since the invention is not brand new. The novelties in the near future will be the affordability of 3D printers and work materials. Internet sites for models will abound, so even downloading models will be affordable.