The cumulative techniques used in 3D printing are complex and the corresponding printed materials are varied. Fused Deposition Molding (FDM) is a method of extruding thermoplastic filament material through a heated nozzle. This 3D printing technology does not require a laser. The equipment used is low in cost, and the process is introduced. There are many types of materials available, such as ABS\PLA. And paraffin-based, relatively cheap and high utilization, is the mainstream technology used in the popular desktop 3D printer.


Let's take the PLA material as an example to explore several factors that affect the accuracy of the product:


In the 3D printing process, there are many factors that affect the accuracy of the product, such as the accuracy of the printer itself, and the setting of process parameters during the printing process.


1) Printer accuracy


The manufacturing and assembly accuracy of the printer itself and the vibration during operation can affect its printing accuracy. For example, the XY plane error, the structure of the printer frame and the stiffness of the material used have a great influence on its stability. For professional users such as designers, there is a heavier print load, and more metal materials contribute to the stability and durability of the device.


2) Process parameters


(1) Temperature


The print temperature includes the extrusion head heating temperature and the hot bed temperature. The heating temperature of the extrusion head mainly affects the bond-stacking property of the material and the fluidity of the wire. Too low a temperature will make it difficult for the material to adhere to the hot bed or to cause delamination between the layers, and at the same time, it will easily cause nozzle clogging; if it is too high, the material will be squeezed to a liquid state rather than an easily controllable filament.


The nozzle temperature and hot bed temperature are important parameters that we need to observe and adjust in real time during the printing process. So we need to choose a machine that clearly shows the parameters of the printing process. OME shows the nozzle and platform temperature in a curve. The advantage is that you can see the temperature changes over time to understand what the machine is in the moment before the error occurs. Not only that, OME smart 3D printer also supports the state of consumables blocking materials, real-time monitoring of printing status, to achieve no material pause printing and alarm.


(2) Nozzle diameter and layer thickness


The diameter of the nozzle determines the width of the extruded wire, which in turn affects the fineness of the finished product. Since the 3D printed material is laid up layer by layer, the layer thickness setting also affects the roughness of the product. If a large-diameter nozzle is used and the thickness of the layer thickness is set, the printing speed is relatively fast, but the finished product is rough; on the contrary, the printing speed is slow, but the finished product is finer. When printing, it is necessary to comprehensively select the size and purpose of the model to properly select the nozzle layer thickness.


(3) Printing speed


3D printing is a process in which the printing speed and the extrusion speed match, and this requires a reasonable match to meet the printing requirements. If the printing is much faster than extrusion, the material is insufficiently filled, resulting in broken wires; otherwise, the fuses are deposited on the extrusion head, resulting in uneven material distribution. Since the material used for the desktop printer is silk, it is only necessary to set the wire diameter and printing speed in the program, without setting the extrusion speed. Print speed has a critical impact on the accuracy of the part. It can't be too fast or too slow. It needs to be set in detail, including the print speed of the outline, the filling speed of the solid, the printing speed of the support structure, etc., and usually The first layer sets a slower speed to improve its finished product