The current paper investigates the influence of the hardware setup and parameters of a 3D printing process on the resulting sample strength obtained through fused filament fabrication (FFF) technology. Three-point bending was chosen as the strength measure for samples printed with the long side oriented along the Z-axis. A single CAD model was converted into NC-programs through the same slicing software to be run on five different desktop FFF 3D printers with filament of the same brand and color. For all the printers, the same ranges of layer thickness values from 0.1 to 0.3 mm and feed rates from 25 to 75 mm/s were planned to be varied. The first four machines considered in the study were off the shelf devices available on the market, and the fifth was a quick prototype of a desktop machine design based on the analysis of pros and cons of the four machines considered. The results of the study show that the hardware setup of a desktop 3D printer can drastically change the influence of basic technological parameters such as feed rate and layer thickness on the interlayer bonding. This means that many of the conclusions drawn from previous studies connecting the technological parameters of the FFF process with the mechanical performance of parts and samples may only be correct for specific hardware setups.
Keywords: Bowden extruder; direct extruder; fused deposition modeling; fused filament fabrication; interlayer bonding.