In the recent years, 3D printing has become a topic of great interest from both academic and the industrial sector through the increasing importance of Industry 4.0. This technology is based on layer-by-layer melting of materials to create a three-dimensional object. It is also known as additive production, and it is feasible through several different methods such as stereolithography, selective laser melting and sintering (SLM, SLS), these are just some of the examples, but fused decomposition modeling (FDM) has become the most interesting technique.This paper seeks to analyze the fracture strength (torque) of coupled gears made out of PLA plastic produced by the 3D printing process. To reduce the number of experimental measurements, the Taguchi L8(27) orthogonal array was used to analyze the influence of factors on two level. Investigated factors were: wall thickness, infill and number of infill lines, layer height, temperature, cooling and speed. Finally, optimization of most influential factors according to maximum torque was preformed, using Taguchi method too.