Strange 3D pint issue

Maybe someone here can assist me. Our 3D printer prints the first layer very nicely (the first image is of the back of the print as an example), but when I come back to check the print a while later it has printed weird “waves” or undulations in the subsequent layers. The second and third images show these errors.
Any suggestions as to what I should look into.
We are using an Ender 5 Pro, PLA filament (1,75mm), bed heated to 50C, nozzle at 200C. The project is a Lithograph being printed at 100% infill. We sliced the model in Ultimaker Cura.


If the waves are perpendicular to the direction in which the filament is being laid down then this could indicate that the rollers on the extruder carriage are out of round (if the waves are spaced regularly) or that the track that the extruder carriage runs on has irregularites (if the waves are not spaced regularly). So check that the rollers and track are completely clean and in good condition.

This sort of fluctuation can also be caused by a problem with the filament feed, but in that case the effect appears as spots and patches, not waves.


Great first layer! For those weird waves, check your infill settings in Cura—tweaking pattern or density might help. Also, experiment with temperature, cooling, and print speed. Ensure smooth Z-axis movement. Hope this smoothens out the subsequent layers of your Lithograph