This article analyzes factors affecting 3D printer resolution and speed, trade-offs between them, printer comparisons, and improvement methods, guiding users to optimize 3D printing processes.
Factors affecting the resolution of 3D printers
(1) Printing materials
In 3D printing, the printing material has a significant impact on resolution. Taking FDM printing as an example, the printing material usually has wires with a diameter of 1.75mm or 3mm. The stability of the wire diameter is directly related to the printing resolution or layer height. Materials with a constant diameter help to produce accurate printing resolution. Different material properties will affect the flow and extrusion characteristics of the material, thereby affecting the final printing resolution. For example, some soft and sticky materials may not be as easy to control during extrusion as stiff and moderately sticky materials, thus affecting the molding accuracy of each layer and ultimately affecting the resolution.
(2) Nozzle diameter
Nozzle diameter is an important mechanical factor affecting printing resolution. In different printing application scenarios, there are multiple diameters to choose from, generally ranging from 0.1mm to 1mm. Smaller nozzle diameters can theoretically provide higher printing resolution. Because the nozzle diameter determines the width of the extruded filament, when the nozzle is small, it can make the extruded material of each layer finer, thus better depicting the details of complex models. However, too small nozzle diameters may also bring some problems, such as easy clogging of the nozzle, affecting the smoothness and continuity of printing, and may also cause a significant decrease in printing speed.
(3) The 3D printer itself
The performance of 3D printers plays a crucial role in resolution. The steps on the z-axis of the printer can achieve printing resolution or layer height. Industrial-grade FDM 3D printers have higher performance than commercial printers and can easily print parts with finer layer heights. This depends on the accuracy of the printer’s movement in the z-axis, the accuracy of the drive system, and the stability of the mechanical structure. If the printer’s movement accuracy in the z-axis direction is low or there is shaking, vibration, etc., the printed layer height is difficult to accurately control, thereby affecting resolution. Printers of different types, grades, and brands have differences in these key performance aspects, such as high-end 3D printers often use better design and higher quality materials in mechanical structure, so they can achieve higher resolution.
Factors affecting the printing speed of 3D printers
(1) Types of printing technology
Different 3D printing technologies have significant differences in printing speed. For example, DLP and LCD printing technologies have advantages over SLA in terms of printing speed. This is because DLP and LCD belong to surface forming technology, which can solidify one surface at a time during printing, just like scanning a piece, while SLA is laser dot forming, which can only solidify one point at a time. Therefore, under the same conditions, the forming speed of DLP and LCD will be faster. This difference in forming method is a fundamental reason for the difference in printing speed. Different printing technologies involve different working principles and physical processes, which directly affect the speed performance of printing.
(2) Printer’s own settings
Printers themselves have some factors that limit printing speed. If the printer has a preset speed, the printing speed will not exceed this set value no matter what. Moreover, each printer has a hardware-level limitation on printing speed due to its different mechanical structure, driving system, heat dissipation system, etc. Taking resin 3D printing as an example, the speed of printing at the system level during the printing process will also be affected by the printer itself. For example, in some printers, the light source passes through the bottom of the transparent resin material tank, and the newly solidified resin needs a cumbersome detachment process before it can continue to solidify a new layer. If the detachment process is slow, the overall printing speed will be affected. Of course, some manufacturers will optimize this process, such as allowing the system to quickly achieve detachment, or using solidification at the top of the resin surface instead of the bottom to increase speed.
(3) Light source intensity (suitable for light-curing printers)
For photocurable 3D printers, resin printing uses a light source to cure photosensitive liquid resin to print 3D models, and the printing speed depends on the intensity of the light source used. Generally speaking, increasing the intensity of the light source can improve the printing speed under other conditions unchanged, but this also means additional costs, such as more expensive light bulbs or power equipment, and may also affect other aspects of printing such as model accuracy. In different photocurable 3D printing technologies such as SLA, DLP, and LCD, although the difference lies in the light source used for curing resin, the intensity of the light source is still one of the key factors affecting their respective printing speeds.
(4) Layer thickness
Layer thickness has an important impact on printing speed and is closely related to model quality. When printing, the required layer thickness determines the printing speed and the required printing time. If the layer thickness is thinner, then when printing a 3D model of the same height, more layers need to be printed, which will greatly increase the total printing time. For example, in a model with a height of 10mm, if the layer thickness is 0.5mm, a total of 20 layers need to be printed; but if the layer thickness is reduced to 0.1mm, 100 layers need to be printed. Although layer thickness may reduce printing speed, it can improve the quality of the finished product, which requires a balance between speed and quality.
(5) Printing materials
The type of printing material also affects the speed of 3D printers. Resins composed of different monomers, prepolymers, photoinitiators, and various other additives directly lead to different characteristics of the materials, including different curing times. Different printing materials have different curing speeds during the printing process due to their different compositions and properties, which directly affects the overall printing speed. For example, some specially formulated resins may cure very slowly, causing a long time to wait for the resin to completely cure each time one layer is printed, thus making the entire printing cycle longer.
(6) The model itself
The structural characteristics of the model itself also affect the printing speed. If the model is hollowed out and there are no more complex details, the printing will be much faster. Because during printing, a model with a simple structure does not need to frequently change the direction and speed of the nozzle during movement, and the nozzle can extrude or solidify the material more uniformly and efficiently. At the same time, reasonable placement of the model will also affect the printing speed. Generally speaking, placing the same model horizontally usually prints faster than placing it vertically, but this may reduce accuracy to some extent. Because some support directions or stress directions of the model change when placed horizontally, this will affect the stability and molding quality during the printing process. However, in cases where speed is the only concern or partial accuracy loss can be tolerated, this model placement method can effectively improve printing speed.
How to balance 3D printer resolution and printing speed
In 3D printing, there is a complex trade-off between resolution and printing speed.
(1) Determine priority based on printing requirements
- In terms of functional requirements
- If it is to produce rapid prototyping models that do not require high appearance accuracy but need to quickly obtain samples for simple functional testing, the resolution requirements can be reduced (i.e. using a higher layer height) and a faster printing speed can be chosen. For example, in the early stages of product development, it is only necessary to quickly verify whether the product’s mechanism is reasonable, whether the components can cooperate with each other, and other functional issues. At this time, a beautiful appearance surface is not needed. In this case, using a larger diameter nozzle, a thicker layer thickness, and a higher printing speed setting can quickly obtain a prototype. At this time, printing speed becomes the primary consideration, and resolution only needs to ensure that the basic shape can be recognized.
- To print functional components, such as small parts in industrial production, these parts may need to be precisely assembled with other components and put into actual operation. At this time, resolution becomes more important. For such functional components that require high precision and good repeatability, even if it means reducing printing speed, resolution must be ensured. For example, when printing some high-precision mechanical connection components or electronic device shells, precise layer height or minimum feature size is required to ensure the accuracy of the components to meet their functional requirements in actual work. Therefore, when printing, it may be necessary to choose smaller nozzle diameters, finer materials (if FDM printing is used), more stable printers, and lower printing speeds.
- Appearance display requirements
- If the purpose of printing is to create items that only focus on appearance, such as figurines or figures, for display purposes, then high resolution is crucial. At this time, printing speed needs to be sacrificed to meet the high-quality requirements for appearance. It requires the lowest possible layer height, suitable small diameter nozzles, and a stable printing environment (to ensure printer accuracy and improve resolution), so that the printed finished product has a smooth surface and rich appearance details, although doing so may result in a longer printing time.
- On the other hand, if it is for quick display printing of some simple appearance items, and the appearance accuracy requirement is not particularly high, as long as the shape effect can be roughly presented, such as some temporary product display models or activity props, etc., a compromise can be adopted at this time. You can sacrifice some resolution appropriately for faster printing speed, and use a slightly higher layer height while ensuring that the basic appearance and simple features can be seen clearly, which can greatly shorten the printing time.
(2) Consider material and technical limitations
- Material property limitationDifferent printing materials have different properties that largely limit the tradeoff between resolution and speed.For example, in FDM printing materials, if a material with high viscosity and soft material is used, when pursuing high resolution (finer layer height), this material may cause printing failure or require very low printing speed to ensure complete printing due to factors such as fluidity and stacking during the printing process. Therefore, in this case, we cannot simply pursue high resolution and ignore the impact of material characteristics on printing speed.For light-cured materials, some resins with longer curing time may not be able to continue to improve printing speed by increasing the light source intensity after reaching a limit point, because the curing time of the material itself limits the improvement of printing speed. In addition, during this process, it may be necessary to consider the negative impact of excessive increase in light source intensity on resolution. Therefore, when weighing resolution and speed, comprehensive decisions must be made based on factors such as the curing characteristics of the material itself.
- Printing technology limitationsPrinting technology is another important aspect of the trade-off between resolution and speed.Traditional FDM printing technology mainly uses the method of stacking filamentous materials layer by layer. In terms of improving speed, it mainly relies on methods such as increasing the movement speed of the nozzle or reducing the layer thickness. However, these operations often affect each other. For example, increasing the movement speed of the nozzle may cause uneven material extrusion, thereby affecting resolution; while reducing the layer thickness can improve resolution, it will also greatly reduce printing speed.SLA in light-curing technology solidifies resin through laser spot, which may require finer laser control when improving resolution, especially horizontal resolution, but this may slow down printing speed.In comparison, DLP and LCD light-curing technologies, although fast, may sacrifice resolution relative to SLA (although they can meet high-precision requirements in some cases), because they are surface molding technologies, and it is relatively more difficult to achieve very fine resolution control when curing resins in large areas.
(3) Consideration of cost and benefit
- Time cost and finished product valueWhen considering the tradeoff between resolution and speed, time cost and finished product value are very important factors.If there is an urgent need for a sample or product, time is very limited, and the product’s resolution requirements are not particularly demanding, then it is more important to increase the printing speed to get the finished product faster, because this can avoid delaying the subsequent workflow or project progress.For example, for some display props urgently needed at the event site, even if the printed product resolution is not particularly high, as long as it can meet the basic visual needs of the temporary display on site, fast printing can be chosen to save time. However, if the finished product has high value, such as limited edition artworks or high-precision medical apparatus components, more attention needs to be paid to resolution. Even if it takes a long time to print, it is worth it because these high-resolution finished products will bring high value returns once successfully printed.
- Equipment and material costsEquipment costs and material costs also affect the tradeoff between resolution and speed.For example, some 3D printers may be equipped with very precise nozzles, precise motion control systems, or high-performance laser devices to achieve high resolution, which are costly. If the resolution requirements for printing tasks are not particularly high, it may not be necessary to use the high-precision printing function brought by these high-resolution devices, which can save equipment costs.Similarly, for printing materials, some advanced printing materials may be able to ensure good resolution and speed, but their cost is higher. If the printing task does not require high resolution and speed, you can choose some relatively inexpensive materials that compromise on resolution and speed to reduce material costs.
Comparison of 3D printers with different resolutions and printing speeds
(1) FDM 3D printer
- Aspects of resolutionsThe resolution of FDM 3D printers has certain characteristics. Its vertical resolution (z-axis direction) is related to the layer thickness. In theory, the resolution can be improved by setting a smaller layer thickness, but it will be limited by various factors in practical operation. In terms of horizontal resolution (x, y-axis direction), it mainly depends on the nozzle diameter and the motion accuracy of the extruder.Generally speaking, the nozzle diameter of FDM printers is between 0.4-1mm, and a smaller nozzle diameter can improve horizontal resolution. However, as the nozzle diameter decreases, it will also bring some problems, such as easier clogging of the nozzle, and greatly reduced printing speed due to reduced flow of extruded material.Relatively speaking, the resolution of FDM printers is lower than other types, such as photo-curing printers when using conventional nozzle sizes and layer thicknesses. However, by improving the nozzle design, optimizing the motion control of the extruder, and using higher quality drive motors, the resolution of FDM printers can be improved to some extent.In addition, when FDM printers print inclined surfaces or complex curved structures, due to the layered stacking method, there may be obvious “step effects”, which affect the surface smoothness and overall resolution of the model.
- Printing speedThe printing speed is affected by various factors. Firstly, the movement speed of the nozzle can be adjusted within a certain range while ensuring printing quality. However, if the control system cannot accurately control the extrusion speed when the nozzle movement speed increases, it is easy to have problems such as uneven material extrusion or broken wires, which will affect the printing effect.Layer thickness is an important factor affecting FDM printing speed. Thicker layer thickness can significantly improve printing speed because the amount of material printed per layer increases and the number of layers to be printed decreases. However, thicker layer thickness will reduce resolution, making the surface of the printed model rougher. In addition, when FDM prints larger models, if the printer structure adopts the XYZ frame structure, the stability of the printer with this structure is generally poor. As the printing size increases, in order to ensure printing accuracy and quality, the printing speed may be automatically reduced to reduce vibration and errors. Overall, compared with other types of 3D printers, FDM printers usually do not have an advantage in printing speed, especially when printing complex and high-precision models, the slower printing speed will be more obvious.
(2) DLP 3D printer
- Aspects of resolutionsDLP 3D printer is a digital light projection technology, and its resolution performance has its own characteristics. In terms of horizontal resolution, it is mainly determined by the pixel density of the digital light source of the projector.The light source of the DLP printer is precise digital pixels, which can provide relatively high horizontal resolution and accurately project very fine pattern shapes. Therefore, when printing flat shapes or models with many detailed patterns on the surface, good resolution can be achieved.In terms of vertical resolution, it depends on the thickness of each cured layer. Theoretically, a thinner layer thickness can be achieved to obtain a higher vertical resolution. However, in practice, a smaller layer thickness may lead to an increase in printing time. If a DLP printer pursues an expansion of the molding size, it may reduce the 3D printing accuracy, because in the process of printing large parts, there may be problems such as uneven light intensity distribution when the light source is projected onto a large area of resin, which affects the printing resolution, especially at the edges and corners where the accuracy may decrease.
- Printing speedDLP is a surface forming technology, which means one sweep is one piece, which gives it a significant advantage in printing speed. Compared with SLA’s laser dot forming technology, it does not require solidifying the resin bit by bit, but can solidify a whole resin layer at once, which can effectively reduce printing time.The printing speed of a DLP printer is also related to the intensity of the light source. When the intensity of the light source is sufficient, it can quickly complete the curing of a layer. At the same time, it is relatively unaffected by the complexity of the model structure. Whether it is a simple block model or a model with a complex hollow structure, it can print at a faster speed as long as it can reach the range of the light source in the resin tank, and its printing speed will not fluctuate too much due to the fault surface in the model.However, the demoulding or cleaning process of the DLP printer after printing may have some special requirements due to its own structure and molding method, which may increase the time of the entire printing process, but compared with the speed of the printing process, this time increase is relatively small.
(3) SLA 3D printer
- Aspects of resolutionsSLA 3D printer is a stereoscopic light-curing molding technology, and its resolution performance is unique. Its resolution is determined by the spot size of the laser beam, and the smaller the spot size, the higher the resolution generated by the printer. For example, the light spot size of a certain SLA printer is 140 microns (0.14 millimeters), while the nozzle diameter of an FDM printer may reach 0.8 millimeters, which is not at the same level. Therefore, SLA printers can often generate more accurate and higher resolution models than FDM printers.In addition, SLA printers apply less force to the model during the printing process, which helps to achieve a smoother surface finish and present finer details. Especially when printing small and fine models, the high-resolution advantage of SLA is more obvious. However, SLA printers are also affected by layer thickness. Although a smaller layer thickness can improve resolution, it will also increase printing time accordingly. Moreover, since SLA printers use liquid resin materials, the properties, fluidity, and light reflection of the resin will also have a certain impact on resolution. When printing larger-sized models, although the current technology can theoretically achieve it, it is necessary to overcome some technical problems such as light scattering and uneven resin flow, which will also affect the maintenance of resolution.
- Printing speedThe printing speed of SLA is relatively slow. Because it relies on laser to outline the shape of objects on the surface of liquid resin, it is a laser dot forming technology that can only cure one dot at a time. This makes it take more time to solidify each dot in turn when printing large-area or complex-shaped models. Although its printing speed in the vertical direction (thickness direction of each layer) can be optimized by adjusting the platform descent speed and other methods, overall its printing speed is much slower than DLP. In addition, the curing time of each layer in SLA printers is also related to the type of resin and laser intensity during the printing process. For some resins with high viscosity or longer curing time, the printing speed will be further reduced. At the same time, when printing large models, if the resin tank is large, it also takes time to adjust the resin supplementation and fluidity, which will slow down the printing speed to a certain extent.
Methods to improve the resolution and speed of 3D printers
(1) Methods for improving resolution
Optimize printing materials
In the FDM printing process, selecting printing materials with stable diameter and high accuracy helps to ensure printing resolution. For example, a good quality 1.75mm diameter wire with small diameter deviation can provide a relatively stable material extrusion amount, thereby improving the consistency of each layer and improving resolution. At the same time, new types of printing materials can be explored. Some specially formulated materials may have better fluidity and molding performance, which can fill smaller spaces while ensuring stable shape, thereby improving resolution. For example, some specially made high-viscosity and good-fluidity resin materials can better fill small spaces in photo-curing printing, reduce uneven layer thickness, and improve resolution.
Precise control of nozzle diameter (for FDM printers)
When possible, choose a smaller nozzle diameter. For example, replacing the original 0.8mm nozzle with a 0.4mm nozzle can make the extruded wire thinner and improve the horizontal resolution. However, during the operation, pay attention to adjusting the corresponding printing parameters, such as reducing the printing speed to avoid material clogging the nozzle and ensuring the coordination of extrusion speed and nozzle movement speed. It is also necessary to optimize some parameters that can affect the nozzle output, such as printing temperature. The appropriate printing temperature can maintain the appropriate viscosity of the material at the outlet, which can ensure smooth extrusion of the material and maintain the accuracy of the material shape, thus helping to improve the resolution.
Printer upgrade and calibration
For the 3D printer itself, its internal key components can be upgraded. For example, for the drive motor and transmission mechanism of the z-axis, if the original low-precision ordinary stepper motor is replaced with a high-precision linear guide rail and motor drive system, it can more accurately control the up and down movement of the z-axis, thereby achieving more accurate layer height setting and directly improving resolution. Regular calibration of the printer is also an essential work to improve resolution. During the calibration process, it is necessary to ensure that the parallelism between the nozzle and the printing platform, the vertical positioning accuracy of the nozzle, etc. are within a reasonable range. For example, use professional calibration tools or print special calibration models to detect and adjust the printer. And to avoid vibration interference to the printer during printing, measures such as anti-vibration pads can be added to ensure the stability of the printing platform and improve resolution.
(2) Methods for improving printing speed
Choose the appropriate printing technology
If you have high requirements for printing speed, you can choose printing technologies such as DLP and LCD for surface forming when conditions permit. Compared with SLA laser dot forming technology, they have obvious advantages in printing speed and can quickly complete the solidification process of the model. For example, when printing a moderately complex and medium-sized model, DLP or LCD printers may save hours or even more time than SLA printers. In addition, for some situations that are suitable for FDM printing but want to improve speed, you can try FDM printing technology designed specifically for fast printing or new printing modes. For example, some FDM printers provide high-speed mode, in which they may use special layer thickness strategies or nozzle movement strategies to improve printing speed, but may sacrifice some accuracy.
Adjust printer internal parameters and settings
Optimize the printing speed according to the characteristics of the printing model. For example, when printing models with simple shapes, no complex hollowing or internal structures, the printing speed setting can be increased. For models with different cross-sectional conditions, if the nozzle can continuously travel a long distance when printing a single independent part (greater than 80mm can be regarded as continuous surface printing), faster printing speed can be used according to the reference principle. Moreover, within the safety range, increasing the light source intensity (for light-cured printers) can also increase the printing speed. At the same time, reasonable selection of layer thickness can reduce the number of printing layers and shorten the printing time within the acceptable range of product quality degradation. In addition, placing the model reasonably before printing to make it as compatible as possible with the printer’s printing actions can also help improve printing speed. For example, placing the rectangular parallelepiped model horizontally may simplify the motion path of the nozzle when printing vertically, thereby reducing printing time.
Optimization and upgrade of printer hardware
Optimizing and upgrading the hardware of the printer can also help improve printing speed. For example, replacing the printer with a stronger driving motor or transmission system can make the nozzle move faster and more stable, thereby improving the overall printing speed. In some light-curing printers, upgrading the light source system to a brighter and more efficient light source can reduce the curing time of each layer and greatly improve printing speed. Optimizing the design of the resin tank or reducing the stickiness of the resin during demolding through technical means can make the new layer of resin rise quickly and cure, which is very helpful for improving the speed of light-curing printers.
