There are several different technologies of 3D printing. In our experiment, we studied FDM method of 3D-printing and the differences in impact work and impact toughness that appear in changing the fill density and angle of inner filling. We also studied which of the named parameters are the best for minimum consumption of material and for the best impact properties. Mechanical properties were tested with the Charpy impact test. Based on the Charpy test, we scanned impact work and calculated impact toughness. Findings suggested that specimens with an inner filling of a 90° angle and 50% fill density use the highest amount of impact work. Specimens with 0% fill density have the highest impact toughness and can be interpreted as specimens with best impact properties for minimum consumption of material.