3D printer - the printing of three-dimensional elements

Normal inkjet printers or laser printers have long been standard in every private household or business office. For some years now, however, 3D printers have also been on the advance of being able to reproduce images - as the name suggests - in a three-dimensional format.

They work with different materials, techniques and results. However, all 3D printers are characterized by the fact that small or large components can be printed dimensionally and then used for various applications.

Appearance of a 3D printer

Optically the 3D printers differ immensely from the normal printer variants, which print pictures in two-dimensional view. A 3D printer is similar to a small injection moulding machine that is generally used in industry to produce plastic parts.

The 3D printer consists of a base, which - depending on the technology - is fixed or adjustable in height. Above this is the pressure chamber, which is usually enclosed by walls made of glass or other materials. The finished component is later produced in the pressure chamber. A print head is required for the component to be printed.

The print head is located above the pressure chamber. The print head resembles a narrow valve or nozzle through which the print material is pressed. The print head can move freely horizontally so that components can be printed completely layer by layer.

The remaining optical properties change from manufacturer to manufacturer. While some manufacturers attach an input screen to the printer, many manufacturers do without such a function and use their own PC to enter data. The manufacturers are very free in the optical organization and at the Design in the exercise.

The data input

In principle, data entry can be done in many ways. While CAD documents are mostly used in industry, private individuals can also use their own 3D scanners for small components, which act like a digital camera.

Explanation: CAD documents are files that have been produced with design programs such as Solid Edge or Solid Works. The term CAD stands for Computer Aided Design and means nothing other than that a component was not constructed on the drawing board, but directly in digital format on the PC. However, such CAD programs are usually very expensive, which is why manufacturers use other tools for private individuals.

Private users can scan existing real objects with a special camera, which then processes the 3D photographs taken and converts them into a print template.

Alternatively, there are numerous 3D templates available on the Internet that can be downloaded free of charge and fed into the 3D printer.

Functions

If a 3D printer is to be purchased, it is possible to decide directly at the time of purchase which materials the printers are to work with. 3D printers do not work with ink and paper, but create three-dimensional objects from either metal or plastic.

The most common 3D printer, which is also intended for private use, is the FDM printer, also known as the Fused Deposition Modeling Printer. In addition, there is the SLA printer (stereolithography printer) for industrial use with epoxy resin. Finally, the SLS printer, which is called a selective laser printer and works with metal, is of great importance.

Although there are many other processes besides these printers, these three variants are among the most common types.

The FDM printer: The FDM printer processes plastics, which are fed into the printer as so-called filaments. Filaments are rolled plastic threads that are then melted in the print head and fed through the nozzle into the pressure chamber. The FDM printer, for example, uses ABS or PLA plastic. While acrylonitrile butadiene styrene (ABS) is used for thick-walled and tear-resistant objects, polyactide is used for simple "plastic" components. Disposable drinking cups, for example, fall into this category. The advantage of ABS is that it is temperature-resistant to just under 220 degrees Celsius and can be used for a wide range of applications.
The SLA printer: The SLA printer also has a pressure chamber, but the liquid epoxy resin is cured selectively in the chamber with a laser. However, SLA printers also work in layers, but the laser can achieve higher degrees of hardness and increased precision. They work with epoxy resin, which is very impact resistant, tough and abrasion resistant.
The SLS printer: In contrast to the other variants, this printer works with metal powder which is sintered in the pressure chamber. This means that the powder is hardened by an addition of temperature and applied in layers. Aluminium powders are often used, but plastic-metal compounds can also be used for increased strength.

The remaining processes (MJM, 3DP, etc.) also work in layers, but usually use different print heads or lasers to process different materials. The choice of material usually also changes the printer used. Printing capacities

printing capacities

The speed of the 3D printers depends on the additional functions of the printer and the object to be printed. The smaller the object, the faster the printer can create the three-dimensional object. The print head can also process round objects or straight components faster than if the component were very angular.

However, the printing times cannot be compared with those of normal laser printers or inkjet printers. A three-dimensional object can take between 15 minutes and 15 hours - depending on the material, component dimension and printer.

If you want to increase the speed, you can buy a 3D printer with additional cooling. This allows the layers to cure faster and the printer automatically works faster.

Accessories

When it comes to accessories for printers, the most important thing is the material used. As already mentioned, 3D printers can work with both metal and plastic. In the following list is listed which materials are used with pleasure and for what they can be used usually.

  • ABS (Acrylonitrile Butadiene Styrene) - for Heat Resistant Components
  • PLA (Polyactid) - for cost-effective series components
  • PA (polyamide) - for components to be reworked
  • Epoxy resin - for impact-resistant components
  • Aluminium - for lightweight components
  • Titanium - for high-quality metal components
  • Co-polymers - multiple use

Co-polymers can look very different because every manufacturer can mix co-polymers with different plastics. A co-polymer consists of several plastics to produce certain properties. Most manufacturers keep the composition secret.

Tip! In general, prints with plastic or metal are relatively odourless. Users will only notice a slight smell of warm plastic. The exception is ABS - ABS constructions can leave a burnt smell during printing, so the printer should not necessarily be placed next to the normal workplace.

Features

3D printers convince in the test by their flexible mode of operation. In industry, such printers are particularly popular when small quantities of spare parts need to be supplied. Due to the low printing speed, the printer is not suitable for series production, but can be used excellently for the construction of prototypes.

Advantages:

  • Printing 3D elements
  • Best use for spare parts
  • Data input via CAD or scan possible
  • Works with metal or plastic
  • Many methods for comparison available

Disadvantages:

  • Cost-effective 3D printers are often inaccurate
  • Low printing speed

Customer segment

As already mentioned, 3D printers can be used in both industry and private households. A 3D printer is used in the industry for spare parts and prototypes - in the private everyday life it is used gladly for gadgets. Play figures for children can be printed or models can be placed in the showcase. The application possibilities are limited only by the own imagination - and in the last step by the construction of the 3D printer.