Fused-Filament Fabrication (FFF)

The first and most commonly known technology is called fused-filament fabrication (FFF). In FFF, a pliant material, typically a thermoplastic such as PLA or ABS, is used as the building material. These materials become soft and moldable when heated and return to a solid state once cool. The material is formed into a long filament that is fed into a heated extruding nozzle within the printer. The heated material passes through the extruder and the extruder is moved through the horizontal plane to draw the layer. The extruder’s position with time is mechanically controlled, which is typically implemented using motors connected to beams that sweep along the width and length dimensions. Once a layer is deposited, the extruder is raised or the building surface is lowered so that the extruder may deposit a new layer of material immediately on top of the previous layer. Proper heating of the extruder and external cooling allows new material to bond smoothly and strongly with existing material. Additional materials that use or simulate materials such as metal may also be used. Advantages of FFF are relatively inexpensive materials, simplicity of the writing mechanisms, and overall lower costs of purchase and operation.