Two bearings provide free angular rotation to the chuck and keep it centered (Figure ). The rotation of the chuck was controlled by a 1.8 o stepper motor with a 20-tooth shaft gear, connected to 60-tooth belt pulley coupled to the chuck by a 2 mm pitch belt. This assembly results in a 1:3 gear reduction. By setting 32 micro steps per step, this configuration allowed for a rotation precision of 0.41 μm. To prevent cylindrical collector misalignment, an additional FFF component and a bearing with a 2.5 mm inner diameter secured the tube at the opposite end. The cylindrical collector stepper motor was operated through the extrusion motor control of the original FFF printer and the distance between the collector and the flat collector was regulated by the original 3 screw-spring system for collector leveling. To increase the heating power of the collector, a 100 W heater was used. The overall cost of the modifications is approximately $500 at the time of writing and this is demonstrated in Supporting Video 1.