![]() ![]() For example, E3D's Volcano hotends can increase the maximum volumetric speed by around 70%, while Bondtech's CHT nozzles can increase the maximum volumetric speed by 30% without the need to modify the hotend. In order to increase the maximum volumetric speed, new hotend and nozzle designs have been developed. Image 3: Volcano hotend, with a larger melting area compared to conventional hotends. Using higher speeds would imply a high risk of missing extrusion and delamination of layers. If we also use another common configuration such as a 0.6 mm nozzle and a 0.3 mm layer height, the maximum print speed would drop to 55 mm/s. The most common maximum volumetric speed of a desktop printer when printing ABS is around 10 mm 3/s, which implies that the theoretical maximum speed at which ABS could be successfully printed using the standard configuration based on a layer height of 0.2 mm and a nozzle of 0.4 mm would be only 125 mm/s. Therefore, for a given printer, the maximum printing speed is also limited by the maximum volumetric speed characteristic of its extruder according to the following ratio: The maximum volumetric speed is related to three variables: This concept, known as maximum volumetric speed, is a parameter specific to each hotend and varies according to the material used. Extrusion volume flow rate limitationsĪnother important limitation in high-speed printing is the maximum capacity of a die to melt and extrude plastic. Video 1: Example of vibration compensation using the input shaping method. ![]() This is similar to the approach used, for example, in noise-cancelling headphones or optical stabilisers. This software-based method means that, once the vibration frequency is known, a sequence of pulses is sent to the motors that cause the spindle to vibrate in an inverse pattern to the resonance, thus cancelling out the spindle vibrations during movement. The most common way of dealing with this problem on desktop FFF 3D printers was based on developing mechanically more stable structures, until Klipper, a free firmware alternative to Marlin, implemented a resonance compensation method based on the "Input Shaping" vibration control method. Image 2: Pattern marked on the surface of a part due to resonance. More stable structures will have higher resonance frequencies and lower amplitudes, resulting in less loss of accuracy and a less visible effect on the surface of the part. The appearance of a wave pattern on the surface of the part.ĭepending on the stiffness of the structure, the frequency and amplitude of vibration varies.This vibration is transmitted to the spindle during movement, with two consequences: Once the structure enters into resonance, it will start to vibrate at a specific frequency characteristic of each printer. At low speeds, printer structures have sufficient capacity to absorb and damp vibrations, however, as speed and acceleration values increase, the risk of a resonance phenomenon increases. Vibrations and their effect on print qualityĪs spindle speeds and accelerations increase, so do the inertias transmitted to the structure and hence the vibrations. Image 1: Industrial FFF 3D printer (left) and desktop FFF 3D printer (right). The thermal behaviour of the printing material.The maximum volumetric flow rate that the printhead is capable of extruding.The loss of precision and quality caused by the vibrations of the structure.This is why the maximum speed that an FFF 3D printer can accept depends on three factors: This is because these printers, due to their cost and compact construction, are more susceptible to vibrations due to movement and their heads, which are more compact than those of industrial equipment, are not prepared to extrude high volumetric flow rates. The concept of high-speed FFF 3D printing generally refers to desktop 3D printers. These new printers promise print speeds up to five times faster without affecting part quality, but how much is reality and how much is marketing?įirst of all, it is necessary to understand the limitations and problems that occur during high-speed printing. ![]() In recent months the concept of high-speed FFF 3D printing has become very popular thanks to the launch of the Hyper FFF kit for Raise3D's Pro3 series and, subsequently, the high-speed printing capabilities of some new models such as the Bambu Lab X1, the Ankermake M5 or the recently introduced Prusa MK4 and Creality K1. ![]()
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