 This paper investigates the mechanical properties of finwalled specimens made from PLA plus bronze composites by fused deposition modeling, FDM. The printing process, geometric measurements, static tensile strength tests, and microscopic examination were conducted. The results show that the tensile strength of the specimens depends on their thickness and printing orientation. Thinner specimens have higher tensile strength than thicker ones, while those printed along the Z-axis have lower tensile strength compared to those printed along the X or Y-axis. Additionally, the presence of bronze particles in the PLA matrix has been found to increase the tensile strength of the specimens. These findings can be used to optimize the machine design and to improve the accuracy of filament deposition. This article was authored by Jersey Bakmia, Tomasz Kozier, and Małgorzata Blażak.