Most people understand the resolution in terms of pixels – how many individual dots make up the screen’s image. However, resolution is also a crucial factor in 3D printing.
Precision
High-resolution prints can be used for various applications, including quality control, reverse engineering, animation and VR, heritage preservation, and jewelry. Unlike accuracy, which refers to how close a 3D printer is to the object it’s creating, the resolution is how fine the details are and can be expressed in microns (thousandths of a millimeter).
Many factors can influence a 3D printer’s resolution, but the most important one is the size of the nozzle used for printing, specifically its diameter. A smaller diameter allows for more precise movements of the print head and enables finer details to be produced. The nozzle’s components, as do the materials used, also affect printer resolution. Another factor is the layer height used for printing an object or how much detail is printed in each vertical inch. Typically, the lower the layer height, the better, but this can vary depending on the model. For example, if the model has a lot of diagonal edges, upping the Z resolution will help create smoother transitions, but this can increase print time and may not improve the quality of the printed part.
Durability
3D print resolution measures the quality, or level of detail, at which your print is created. This is determined by the printer’s movement on the XY and Z planes, with smaller movements yielding higher resolutions. It also includes the smallest movement the deposition technology can make in a single layer.
In extrusion-based 3D printers, the resolution is also related to the layer height or, in other words, how thin a layer is. Increasing the resolution makes the layers thinner and the printed surface smoother. This is especially important for curved or diagonal surfaces, where the transition can be more visible than straight edges. A good resolution is typically around 100 microns, providing a great result for most prints. Lower resolutions are possible, but the trade-off is that printing your model will take much longer. For this reason, higher resolutions are usually used for very intricate and highly detailed models. In addition to the printing resolution, several other factors contribute to the final quality of a print. For example, the material will have a certain melting point, and the temperature of the extruder and heated platform are also crucial for getting the best results. Keeping the printer clean and well-lubricated will help as well.
Speed
When most people hear the term resolution, they think of the pixel-based measurement used on digital screens—the higher the number, the more detail a screen can display. However, a few other types of resolutions come into play in 3D printing. For example, a printer’s XY resolution measures its smallest movement on the two parallel planar planes to the build platform. Most printer spec sheets list only the Z-axis movement, or layer height, as their resolution. Still, it’s important to remember that a finer XY resolution is just as crucial for quality prints.
A common misconception is that a higher resolution means thinner layers, but this is only sometimes true. It depends on the size, shape, and detailing of the model as well as the XY resolution of the printer. Often, thinner layers lead to more time, artifacts, and errors during the print. On the other hand, a high-resolution printer will print parts faster than a low-resolution printer because it can make each print layer smaller. For small prints (under 4cm tall), a layer height of 0.25 to 50% of the nozzle size works well—just be sure to adjust other settings that affect the flow rate to avoid under-extrusion or overheating. A higher resolution is generally better for larger models because it allows the print to cool down quickly and create stronger, stiffer parts.
Efficiency
Only some prints must be high-resolution, depending on an object’s size, shape, and detailing. This decision will largely come down to how the part is used. For example, if an industrial 3D printer prints large, bulky parts that won’t be exposed to wear and tear, the need for a high-resolution finish will not be as big of a concern.
The resolution also depends on the raw materials used in a 3D printer. Powder-based printers will have a lower resolution than liquid-based printers. This is because the layer height of powder-based printers is determined by the particle size of the raw material, while the printer itself defines the layers in liquid-based printers. A 3D printer with a higher resolution can make finer layers, which creates more intricate prints. This can lead to more detail and a smoother transition between different areas of the print. However, it can also lead to a longer printing time. So it’s important to weigh the pros and cons of a higher or lower resolution when designing your prints.
The most common resolutions for commercial metal 3D printers are 25 microns and 100 microns. Higher resolutions can produce detailed models, while lower ones produce more durable prints in less time.