On the effect of printing orientation on the surface roughness of an additive manufactured composite vertical tail

Additive manufacturing (AM) enables the production of customised and sophisticated components; Fused filament fabrication (FFF) is a widely used and cost-effective AM technique. Nevertheless, the use of FFF for aerospace and aeronautical applications is often impeded by the inadequate surface finish it imparts to the produced components. This work aims to demonstrate that, with careful calibration of process parameters and build orientation, FFF can produce aerospace components with low surface roughness. This could enable FFF to be used in aeronautics, allowing the benefits of lightweighting structures using metal replacement thermoplastics and variable infill to be exploited. In this study, rudder sections of a UAV tailplane were produced using FFF and lightened through variable internal infills, thin thicknesses, and a polymer for metal replacement. By setting different printing processes, such as infill percentage and orientation, a configuration with 10% of linear infill which results in a 97.5 g component was identified that exhibits suitable surface roughness for aerospace applications and a weight saving of approximately 50% compared to an equivalent metal volume.