YouTuber tests different infill rates for 3D-printed parts

The YouTube channel Tech Ingredients has conducted a detailed experiment to investigate how different filling levels and material combinations affect the mechanical properties of 3D-printed components. The test provides valuable insights for users who want to optimize their prints in terms of stability and weight.

The study focused on rectangular 3D-printed test blocks made of PLA (polylactide) with different infill levels (infill from 10% to 100%). Tech Ingredients also tested a PLA-carbon fiber mix. The mechanical properties were analyzed using a hydraulic press setup. The resistance to a defined bending deformation was measured in order to evaluate the stiffness and strength of the prints.

A force sensor (load cell) recorded the applied force, while an electrical contact mechanism registered when a deflection of 3 mm was reached. By weighing the test specimens, the relationship between weight and mechanical load capacity could be determined.

The test results show that the degree of filling does not have a linear effect on the strength. While only a moderate increase in stiffness was observed between 10 % and 50 % filling, the values increased sharply from around 70 %. An almost solid component (100 % infill) was more than three times as stiff as one with 50 % infill. However, the part weighed considerably more.

It is interesting to note that a low degree of infill from around 10 % is already sufficient to mechanically couple the outer structures. This means that components with 10 % to 50 % infill only show slight increases in stiffness. However, they remain considerably lighter compared to solid parts.

Another test analyzed PLA made with carbon fibres (PLA-CF). This material showed 50% higher stiffness than standard PLA, while having almost the same weight. PLA-CF is a particularly useful alternative for applications where low weight and high mechanical strength are required.