What is the layer height?
In the beginning, I thought that it was only related to quality, but now I know it’s not like that.
Layer height is connected to extrusion speed, printing urgency, and mechanical resistance.
Layer height is the thickness of one printed layer in millimeters.
One single layer is nothing more than a set of 2D coordinates, which are written in the Gcode.
The layer height shall not be thicker than 3/4 of the nozzle diameter.
The reason simple: if the layer is bigger, you end up having a delamination problem, meaning at some parts, the layers don’t blend in together.
When we use a 0.4mm nozzle, the maximum layer height should be 0.3mm
What is “Extrusion Speed”?
Good question. It’s a setting that does not exist inside the slicer, but you can check on it by looking at the pulley that carries the filament inside the 3D printer. Based on how it spins, you can understand if the printer will make it to the end of the job.
When the printer is used improperly, it tends to tire. Otherwise, if this parameter is being controlled, the printer will work smoothly with less overuse.
Let’s take this example to understand the standard extrusion speed.
Create a new Gcode with 0.2mm layer height and 50mm/s printing speed (which is the maximum speed the Hotend can bear).
Temperature is set accordingly to the material type, but keep in mind that if we’re going the full speed you should add +15 degrees in addition.
PLA is usually set at 205°, but this time only make it 220°. The reason is because of the high speed, the nozzle needs to melt quickly the filament.
The quality of the print is related also to the layer height. The higher the layer is, the poorer the quality.
When the nozzle is 0.4mm, the maximum layer height is 0.3mm, meaning the printed layers will be thicker and more visible. Each mm will be made up of 3.3333 layers.
On the other side, when you set the layer real thin, lie 0.06 mm, the 3D entity will have a great quality. Clearly, it’ll take more time to print the object because of the low speed.
Now, let’s practice what we’ve just learned
First exercise: import a 3D model (small, if possible) into Cura 3D.
Set the parameters as follows:
This is what happens when Cura finishes loading the file.
It shows us time and weight fo the future object. Keep in mind that these values are not 100% trustworthy, because most of the times there’s a gap of 15% between software and actual time/weight.
Second exercise: change basic printing parameters as follows to see how the estimated time and weight change. Please, notice how the printing speed increases.
Third exercise: change the basic printing settings again as follows.
Anew, we notice how the printing speed increases. Now we know it means the quality will be lower.
What you’ll notice the most is the overall printing time. According to your (or your client’s) needs, you set different parameters, making the printer work faster or slower.
Thanks to the huge number of tests I’ve run, I can assure you of the importance of managing the layer height. It can save you a lot of time, especially when your object takes up hours and hours to be made.