This paper presents a parametric study of classical additive 3D-printing settings for use on conductive filaments in applications for high-frequency topologies. First, a wideband characterization was conducted, printing a microstrip transmission line using a conductive filament with variations of typical 3D-printing settings, such as layer height, infill percentage, and infill pattern. The measurement results show a dependence on the high-frequency transmission parameters with respect to the infill percentage and the infill pattern. Finally, two antennas were 3D-printed using conductive material, a microstrip patch, and a low-weight pyramidal horn antenna. The results for the patch agree with the losses found on the line measurements, while the low-weight pyramidal horn exhibits no major differences compared with its equivalent antenna, made using perfect conductors.