3D-printed metal parts manufactured by laser powder bed fusion method are considered in this article. Uncertainties regarding the homogeneity of powder raw material properties and the obtained mechanical properties of the 3D printed parts using a tool steel are investigated. A demonstration tool steel part is characterized in terms of geometry and shape limitations, chemical composition, microstructure, roughness and hardness, with the purpose of assessing the material homogeneity, the effect of heat treatments and the mechanical performance of 3D printed parts that can be used for the production and replacement of critical mechanical components using conventional manufacturing processes.