Choosing the best nozzle diameter and layer height for your model...
The nozzle diameter directly affects the extrusion diameter of each line in a 3D print and directly determines layer width or the 'wall thickness'. The most common standard nozzle sizes for most 3D printers is 0.4mm. It makes for a great all-rounder, a good middle ground between speed and quality.
A larger diameter nozzle such as 0.8mm lays down wider perimeter wall lines. This means that it uses less lines than a smaller-diameter nozzle to print a wall of the same thickness. A nozzle with a larger diameter also allows prints to have an increased layer height. A good rule of thumb is layer height should be 80% of nozzle diameter, higher than this the layers will not adhere well. Combining these two effects leads to a noticeably shorter print time of solid models when larger diameter nozzles are used.
Layer height is the height of each layer of plastic extruded when printing. This setting is adjusted in CURA and will directly influence the print's speed, resolution and surface finish.
A larger layer height means the printer doesn’t have to print as many layers to achieve the same total height, resulting in a much faster print. Generally, increasing layer height will decrease the resolution and quality of your print. This “hack” is therefore better for large prints, where close-up details will either be ignored or touched up during any post-processing.
To summarise a smaller layer height and or smaller nozzle diameter is better:
- When part detail, resolution, and quality is a high priority
- When surfaces must be smooth
- When printing small, intricate parts
- When printing parts with curved sides (to avoid visible layer lines)
Conversely, a larger layer height is better:
- When a shorter printing time is a priority
- When printing parts with straight sides
- When post-processing techniques like sanding can be used to reduce the appearance of layer lines