Printer feeds inconsistent filament

Hello all,

Since last December I am a (somewhat) happy owner of a Vertex K8400.

I have tried a couple of prints since and discovered that the prints are not as they suppose to be. I think that I have found an issue with the feeding of filament, the motor stops every time for a few seconds and continues, this can be seen immediately at the print.

I also made a short video which shows the behavior of the feeder motor:

I have tried several things, but nothing changed. As you can understand, I am a nooby and really need your help to figure out how I can print solid prints.

Thank you in advance,

It is actually hard to say what happens by just looking at the extruder. My guess is, that the printer is doing a retract of the material while moving to a different position to avoid stringing, hence the extruder runs backward a bit very quickly and then hesitates until the print head has reached the new position. Depending on the software you are using for slicing, this might be too much retract which could lead to holes in the print.

dukestah, thanks for the reply.

If you check the picture, you can see the period that the extruder did not supply any filement (left corner) layer is very very thin. I do not think that there is a retraction of filament on that corner. It is also not the starting point of the first brim layer, it was after a couple of seconds that the printer started printing the brim of that piece (starting point was on the right side of that piece).

I use Cura to create the print file.

Yesterday evening I have unloaded the filament and run the program normally, but the extruder motor didn’t work at all. I do not know if this is because the printer detects that there isn’t any filament and that the extruder does not run as part of a “safety” feature?

Can someone confirm that this behavior (extruder stops for a couple of seconds between feeding filament on the same continues layer) is not normal?

Additionally, I would like to try a print without using my computer/own models. Who would be so kind to share their print file with settings (gcode) that have worked without issues.

Many thanks in advance.

Could someone be so kind to check if my gcode file is correct, by either printing for a couple of minutes or just review the programming? Google Drive - XYZ calibration cube

Other question, how to be sure that the printer itself has no settings saved? There are 2 reset buttons (1 near the display and 1 underneath the right filament roller), but I cannot find out what each button does or that they both do the same job. I would really like to put the printer to factory settings at this stage.

Any help is highly appreciated!