Today we are dealing with a new problem, which has several causes and symptoms: ” extruder kliking “. 3D printing not only offers an infinite number of satisfactions, but it can also cause problems, especially when it comes to amateurs and amateur printers.
Extruder Clicking is one of the most common problems we face when starting a 3D printer for the first time, most likely if we are starting a 3D printer in KIT that has never been tested before.
What if extruder clicking?
In simple words it is said that “the extruder clicks” when the motor on which the pulley that should push the filament is mounted is not able to counteract the force and goes back of bang instead of continuing the turn. This problem must be searched to the origin of the motors used in the 3D printing. These are called “stepper motors” and just through a series of steps they move the motor shaft. The motor clicks when it cannot win the force necessary to make a given effort and loses a step. If in the meantime (matter of tenths of a second) the situation has changed it starts to work normally again otherwise it will continue to lose steps. Normally some lost steps do not damage the engine, but certainly damage the prints. You need to fix it as soon as possible.
As we said before, the motor loses its pitch when it cannot counteract the force needed to make a certain movement. Specifically, this happens for several reasons:
What can make the extruder clicking?
- The nozzle is too close to the plate – In this situation the nozzle skims the plate and therefore the extruder cannot push and release the material. This clogging causes the force the motor has to exert to increase considerably and the click may occur. The closer the nozzle is to the plate, the harder it will be for the filament to escape. We can go from a situation in which we will find a series of pulley backslides and zero extrusion to situations in which only a few steps here and there will be lost. In all cases an adequate leveling of the plate and if necessary a setting of an offset (distance between nozzle and plate) greater are necessary.
- Too low hotend temperature – If the temperature is not high enough, the filament will have difficulty melting and will remain semi-solid. It will be very tiring for the motor to push a filament about 2mm out of a nozzle just 0.4mm wide. If you notice that your extruder clicks as first test raise the temperature at least 10 degrees, and check the behavior.
- The motor can’t push – It can happen that the motor simply cannot push the filament. With Bowden extrusion systems, the force required to push the filament remotely increases significantly. In most cases you can remedy this by increasing the working voltage of the motor. You’ll squeeze it a bit more and increase the power as much as possible. In the Blog you will find an article dedicated to the regulation of the Vref (Reference voltage). The article explains how to increase the power of the stepper motor. The increase in power has as only contraindication the increase in temperature, so it is advisable to monitor constant temperatures for the first hours of printing. You can easily monitor the temperature at regular intervals with a digital infrared thermometer, and if necessary add heat sinks on the drivers, heat sinks on the motors and fans (just pick up right voltage fans).
How do I know if I have the problem of extruder clicking?
Normally you notice this problem, in the absence of a marked underextrusion, thanks to the typical noise of the pitch loss! Which gives the name to this problem: the Click.
If we stretch the ear to the extruder we will hear a noise, normally at regular intervals. Tic – tick – tlick – click, call it whatever you want.
Looking at the small motor shaft we will notice that at the noise it will take a small step back. Visually, however, if the loss of pitch is small we will find it very difficult to recognize it. That’s why step loss detectors were born.
The extruder spinner, are printed in 3D and positioned on the crankshaft. Their function is to make the movement of the motor more visible, even if they exist with nice shapes, whose ornamental function surpasses the usefulness of revealing the loss of step.
Here are some examples of these printable spinners:
What problems can the extruder clicking give and how do I solve them?
The main problem with the extruder motor struggling to turn is the lack of filament on the plate. The deposited filament, according to the gravity of the problem, goes from nothing to a slight underextrusion.
In any case, the difficult part is to identify the problem, as once identified it is immediately solved.
In fact, it will be enough to leave more breath between the nozzle and the plate, raise the temperature or give a little ‘more brio to the stepper motor and this problem will be completely solved!