Industrial 3D Printers/Sand 3D Printers/Binder Jetting Additive Manufacturing Guangdong Fenghua Zhuoli Technology Co., Ltd , https://www.fhzl3dpequip.com
The fused deposition molding technology (FDM) mentioned at the beginning is the mainstream technology used in desktop 3D printers. Its working principle is to melt and extrude filament-like thermoplastic materials through nozzles to polymers such as ABS\PLA. Paraffin wax is the main material. In fact, in the 3D printing process, there are many factors that affect the accuracy of the finished product, such as the printer's own precision, printing temperature, printing speed, materials, etc., we look at each one.
Printer's own accuracy
In fact, this has already been decided at the beginning of the purchase of 3D printers, so be sure to check the selection before purchasing the printer. Then, the manufacturing and assembly accuracy of the 3D printer itself and the vibration during the work will affect its printing accuracy. Different from ordinary printers, X and Y can be moved in two directions. In addition to X and Y, 3D printers also increase the longitudinal movement of the Z axis. Any movement of the wire is the mutual friction between the components, and there will always be Subtle deviations. For example, XY plane error, printer frame structure and the stiffness of the materials used will have a large impact on its stability. For those professional users, choosing a heavier print load and more metal material will help the printer's stability and durability.
In addition, the diameter of the nozzle also determines the width of the extruded wire, which affects the fineness of the finished product. It should be known that 3D printing is to construct objects by layer-by-layer printing. Therefore, the layer thickness setting also affects the roughness of the finished product: large diameter nozzles are used, and the layer thickness is thicker. Although the printing speed is faster, the finished product will Rough; on the contrary, the printing speed is slow, but the finished product is more refined.
Printing temperature
The printing temperature we are going to say here actually includes the nozzle temperature and the molding chamber temperature. Among them, the nozzle temperature determines the bonding properties, packing properties, wire flow rate and extruded wire width of the material. Therefore, the nozzle temperature should not be too low or too high. Too low, the viscosity of the material is increased, the speed of extrusion is slow; too high, the material is biased to a liquid state, the viscosity coefficient is reduced, the fluidity is enhanced, and the extrusion is too fast to form a precisely controllable filament. Therefore, when setting the temperature of the nozzle, it should be selected within a certain range according to the properties of the selected wire to ensure that the extruded wire is in a molten flow state.
The temperature of the forming chamber will affect the thermal stress of the formed part. Although the high temperature helps to reduce the thermal stress, the surface of the part is easy to wrinkle. If the temperature is too low, the quenching of the wire extruded from the nozzle will increase the thermal stress of the formed part. It is easy to cause warpage of parts. In order to form smoothly, it is better to keep the temperature of the forming chamber at 55 °C when printing ABS, and the PLA should be kept as air and heat as possible, and should not be kept warm.
Layer thickness and compensation
The layer thickness refers to the layer thickness (or layer height) when sliced. Each layer has a certain thickness, which will produce visible steps on the surface of the formed product. The higher the layer thickness, the more obvious the texture will affect. The dimensional error of the formed body and the roughness of the surface. For FDM technology, this is a principle error that does not completely eliminate the step, but can be improved by setting a smaller layer thickness.
The compensation amount refers to the distance between the actual machining contours of the pieces. For those models with high precision requirements, the general modeling should try to give compensation, especially the inner hole, and the setting and compression of the compensation amount. The diameter of the wire, the performance of the 3D printer, etc., should be explored slowly.
Extrusion speed and filling speed
In the case of a reasonable matching of the filling speed, the larger the extrusion speed, the larger the cross-sectional width of the extruded yarn; when the extrusion speed is increased to a certain value, the extruded filament may adhere to the outer conical surface of the nozzle, The outer surface of the model affects the appearance. When the filling speed is faster than the extrusion speed, the material will be broken due to insufficient filling, which is difficult to form; on the contrary, the filling speed is slower than the extrusion speed, and the fuse is easy to accumulate on the nozzle and the forming surface material is not distributed. Evenly, the surface appears flawed, which affects the print quality. Therefore, the filling speed and the extrusion speed should be within a reasonable range.
Where does the error in 3D printer come from?
With the increasing popularity of 3D printing technology, more and more ordinary users can access 3D printing technology and understand the charm of 3D printing. However, the prospects are good, but they have to worry about the accuracy of their printing. So, what factors will affect the printing accuracy of 3D printers? In this issue, we will take fused deposition molding technology (FDM) as an example to discuss with you several factors affecting the accuracy of 3D printing products, and hope to help you 3D printing enthusiasts.