The application area of 3D printing or additive manufacturing has been rapidly spread into many fields including fashion. The most common process or apparatus for 3D printing, i.e. fused deposition modeling (FDM), has a simple extrusion system using polymer filaments. In the extrusion system, a polymer filament being 1.75 or 2.8 millimeters in diameter was squeezed into a hot small nozzle and the polymer was immediately melted and extruded from the nozzle. The extrusion system is basically applicable to small-scale experiments of melt spinning with installing a take-up roller into the FMD 3D printer. Hence, the spinning of conjugated fibers was conducted utilizing the extrusion system equipped in the FMD 3D printer. The modified filaments having unique polymer arrangements, for example a spiral arrangement of bicomponent polymers, were extruded via the FDM process to manufacture novel conjugated fibers. The characteristic and unique spatial arrangements of the bicomponent polymers were observed in the extruded fibers with an optical microscope.