For some applications, 3D printed parts usually do not have satisfactory mechanical properties, so to broaden their usage, additive technologies should be combined with the well-known metallurgical processes, such as investment and others casting techniques. 3D printing developers persistently introduce new base materials and strengthening fluids which may cause different surface roughness. Therefore, in this paper, the authors have tested the roughness of 3D printed samples strengthened with common, but also with alternative fluids. Measurements proved that fluids do have significant influence on the roughness
