I have the same exact problem. But anywhere with walls too. All my holes in every model.


I am using a Monoprice Maker Select Plus


I have been battling this for over a month now. Lots of research and experimenting and I just can't figure it out.


The pictures included are printed using Cura's default "draft quality profile" for PLA. One sample has wall thickness of 1.2 and the other is 2.4. So the issue is more obvious in the 2.4 mm wall thickness. So I conclude, the more walls, the more worse the problem. I've played around with the usual settings (temp, speed,..). Things that I have tried so far: Speeds from 15 to 60, Temps from 190 to 205 (surface quality begins to fade beyond 200), optimize wall printing order, skin overlap, changing nozzle + ptfe tube in case of clogs, taking apart hotend and cleaning, cleaning extruder gears, checking resistance from spool holder, using different filaments. The one setting that has made a difference so far is the "Flow Rate". At 110% Flow Rate, this issue disappears. Unfortunately, I've come to realize that this is not a proper fix. At this setting, my tolerances and precision is out of wack. And the top surface is becomes significantly uneven because of all the extra material extruded. I am very desperate for a solution as I have fought this for way too long.
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