Troubleshooting: Extruder Motor or Encoder Error

It might happen that you are facing the following error message on the display of your Filament Maker, along with it shutting off: “Motor or encoder error”. There are multiple possible causes for this, which are described in this article, along with how to act accordingly and hopefully fix the issue. The Motor or Encoder error refers to the extruder screw not being able to rotate anymore.

In case you are currently extruding a high-performance polymer, it is very important to act quickly, and not let the material harden out inside the extruder, but remove it as soon as possible. For example, if you are extruding PEEK, this error is showing, and you do not know what to do, it would even be a smart move to call our office and ask our service department directly.

1. Too low temperatures

The first and most obvious cause that has to be looked upon is the extrusion temperature. In order for the extruder screw to be able to rotate consistently and produce an output, the material inside must completely melt. If the material is not completely molten, the screw is stuck and this message will be displayed. Please check the technical datasheet of your material, or consult the supplier, to find out at what temperatures the material should be processed. In all cases the material has to reach temperatures above it’s melting point, but sometimes you might have to increase it even more well above this point – you could try increasing the temperatures with steps of 10 or 20 degrees Celsius, and try turning the machine on again. Please be careful not to increase the temperatures too much, or have the material inside the extruder for too long at these high temperatures, because the material can degrade inside. This degraded material can be quite difficult to remove from the system.

2. A problem with the encoder(disk)

The encoder is a small disk that is attached to the screw and gearbox, and rotates along with it. A sensor can detect how fast the encoder is rotating, and based on this the machine can see if the screw is rotating at the correct/set RPM. If this disk is somehow damaged or misaligned, the reading is not accurate anymore, and the machine shows the error on the display.

By clicking the following link you can find a manual on how to access the encoder: Encoder replacement manual

Once you have opened up the machine, you can check if the encoder disk is still intact, and aligned as in Figure 1.

Figure 1, Encoder alignment

3. A problem with the motor

If the encoder disk is still intact, and aligned perfectly in the middle, it is a good idea to install a diagnostic test firmware on your Filament Maker. With this firmware the exact issue can be analysed, and we can find out what is causing the “Extruder motor or encoder problem”. For this you would need to of course install the firmware, which can be downloaded here:

Diagnostic Firmware

This zip file contains the diagnostic firmware (FeFirmware-v1.3.1-diag.hex), the 3devoUpdate tool, which is used to upload the firmware to the Filament Maker, and a PDF which explains how to perform the diagnostic test.

When the FeFirmware-v1.3.1-diag.hex is installed on your filament maker, you can press in the menu on ‘Start diagnose’.

Always make sure that the Arduino program is on for creating and saving the log file from this diagnose, which you can send back to service@3devo.com so we can analyses the results.

4. The extruder is clogged

If you are working with a high performance polymer, or a lot of additives for example carbon fibers, the risk of clogging the extruder is considerably higher. In the case this happens, you might get the error message “Extruder motor or encoder issue”, or “Extruder motor current too high”, or you are just getting no output from the extruder anymore.

When using these types of exotic materials, it is strongly advised to remove the material as soon as possible from the extrusion mechanism, by purging it (https://support.3devo.com/purging-your-filament-maker/). This can prevent having to send the machine back to 3devo for repairs, and having to remove the extruder screw.

If it is difficult to purge the machine clean from this material, because this message keeps coming up, you could try the following things:

  1. Increase the temperature of Heater 1 (usually 20 degrees C should be enough).
  2. Remove the nozzle to relieve some pressure, and let the material flow out more easily. On this page is explained how to remove the nozzle: https://support.3devo.com/nozzle-replacement/.
  3. Set the screw speed to 15 RPM, to generate some more pressure and force out the clog.
  4. Force feed the purge material into the extruder with a stick. For this you will have to remove the two bolts closest to the hopper, to be able to slide out the grid/mesh, so you can access the opening of the extruder. Then, try forcing in the cleaning pellets with a stick (roughly the size of the opening), to make sure they go in and push out the other material.