Lately, I've been having a problem with the surface of my prints. As shown in following picture:
Printing material is PLA. I've changed the print core (this is the terminology, Ultimaker uses for their hot end for e.g. Ultimaker 3 and 5; these cores come in different nozzle sizes and for different materials) but even with a different print core it happens from time to time (although less frequently). To me it seems like the extruded stops printing for a while and then continues. I've not been able to catch it while it happens though. Any thoughts?
