Why are support structures necessary in FDM printing?

Support structures are crucial in Fused Deposition Modelling (FDM) printing because they help in building certain complex geometries. When a 3D model has overhangs or intricate features that cannot be self-supported during the printing process, support material is required to provide stability. Without supports, the melted filament may droop or collapse under its own weight before it has a chance to solidify properly.

For complex shapes, such as bridges or structural elements that have large voids or need to extend outward, these supports temporarily hold the filament in place while the layers above them are being printed. After the print is complete, these supports can usually be removed easily, leaving behind the intended design. In this way, support structures facilitate the creation of intricate designs that otherwise would not be possible, enabling greater creativity and complexity in 3D printed objects.