Rotary Vane Attenuator is considered an industry standard in precision waveguide attenuators. These attenuators exhibit high accuracy, repeatability and reliability. In this paper, the design and fabrication of a rotary vane attenuator using additive manufacturing techniques is presented. The use of several materials to fabricate the lossy septum is discussed. ABS has been used to design all mechanical and waveguide parts. Waveguide parts has been metallised using a dual component spraying technology. Measurements has assessed the validity of the manufacturing process.