Fused filament fabrication

Fused filament fabrication (FFF), also known as fused deposition modeling (with the trademarked acronym FDM), or filament freeform fabrication, is a 3D printing process that uses a continuous filament of a thermoplastic material. Filament is fed from a large spool through a moving, heated printer extruder head, and is deposited on the growing work. The toolhead, also known as printhead with the heated nozzle is controlled by a computer executing g-code files that are generated by a slicer which generates movements to match a 3D file. In one common design, the toolhead moves in two dimensions to deposit one horizontal plane, or layer, at a time; the work or the print head is then moved vertically by a small amount to begin a new layer. "Fused filament fabrication" was coined by the members of the RepRap project to give an acronym (FFF) that would be legally unconstrained in use.

Fused filament printing has in the 2010s–2020s been the most popular process (by number of machines) for hobbyist-grade 3D printing because of its relatively low cost and ease of use. Other techniques such as photopolymerisation and powder sintering may offer better results, but they are much more costly.

The 3D printer head or 3D printer extruder is a part in material extrusion additive manufacturing responsible for raw material melting or softening and forming it into a continuous profile. A wide variety of filament materials are extruded, including thermoplastics such as acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), polyethylene terephthalate glycol (PETG), polyethylene terephthalate (PET), high-impact polystyrene (HIPS), thermoplastic polyurethane (TPU) and aliphatic polyamides (nylon).