3D printing – Additive production for prototype construction

 

For EnviroTechForge product developments we settled on the 3D printing process (or additive manufacturing) to get faster and more cost-effective developments of casings, fixtures and complex building parts. In this process, material gets added layer by layer in a three-dimensional space.

 

 

The benefits of 3D printing are…

 

environmental aspects: resource-saving material usage, since materials from full material with big cavities would result in large quantities of material waste. During the process no coolants or lubricants, which would pollute the environment, are applied. Furthermore, no transport emissions apply, because the product can be sent digitally and printed locally.

 

technical aspects: you don’t require a big machine pool of drilling-, grinding- or milling machines to achieve the needed components. Therefore, the cutting processes are not needed. This saves acquisition costs and time, since you don’t require timely trainings to the different production processes. With 3D printing it is possible to produce complex and self-contained, which would not be possible with traditional machines.

 

creative aspects: there are almost no boundaries when developing products on a 3D printer – in our case, our prototype construction is completely covered. Furthermore, ideas can be shared digitally quickly and the product can be printed and tested locally everywhere in the world.

 

 

The biggest disadvantage with 3D printing is the completion time until a print is finished.

Figure 1: printed "Raspberry Pi Case" with EnviroTechForge logo
Figure 1: printed "Raspberry Pi Case" with EnviroTechForge logo

 

How is a building part manufactured with a 3D printer? 

 

In a first step we need a three-dimensional digital model. This can be designed with a multitude of 3D drawing programs. The model could be saved as a STL-data format, which is one of the most used 3D data models.

Figure 2: 3D CAD program for 3D modeling
Figure 2: 3D CAD program for 3D modeling

 

Secondly, this 3D file will be translated into the so-called G-code by a slicer program. In the slicer program motion sequences, temperature specifications of the heating, extruders and much more can be adjusted, so that the 3D printer can manufacture the building part as ideally as possible.

Figure 3: Slicer software from 3D printer with multicolored 3D component
Figure 3: Slicer software from 3D printer with multicolored 3D component

 

In a last step, the generated G-code is transmitted to the control of the 3D printer. This happens via an SD-card or through a direct connection of slicer and 3D printer. By the way, the G-code is readable, especially for programmers of CNC, since it is similar to the G-code from the CNC world. Through this it is possible to quickly adjust the extruder or the speed before printing, without having to re-generate the program in the slicer.

Figure 4: G-code file opened in a text editor
Figure 4: G-code file opened in a text editor

 

How can different colours or materials be printed in one product?

 

There are two possibilities to combine colours and materials. For one, the so-called “manual filament change”, where the printer pauses and the extruder is manually un- and reloaded with new materials. But there are 3D printers with multiple extruders, therefore (according to the number of extruders) multiple colours and/or materials can be printed at the same time. Please pay special attention that the Z-highs of the jets are explicitly referenced.

 

We work with an “automatic filament change”, wherein a supply unit can print up to five different materials automatically. This enables us to for example print our multi-coloured logo on our products.