Anyone know what the most likely culprit for this PLA symptom is?

Anyone have any idea what might cause this sort of issue on PLA? I run into it frequently, but ONLY when all of the following points are true: - the print has multiple parts, so the extruder spends a decent amount of time off of any given part (only one part from this print is pictured) - the affected part(s), like the picture above, have a relatively steep outward overhang, extending over the build plate - the outward overhang part is relatively narrow, as seen from a top view The 4028 fan obviously has pretty massive airflow, so is it possible to have too MUCH cooling for PLA? Anyone ever had a similar problem and solved it without just turning the speed waaaayyyyyy down?
No description
5 Replies
mazas
mazas4mo ago
I get similar issues with ABS if do not use enough of cooling. And on the other end, too much cooling on PLA caused the layer bonding to suffer, but I’ve not seen it cause curling up like that.
MONSOONO
MONSOONO3mo ago
Cooling things fast can cause cooling artifacts. So more cooling wont necessarily fix the issue. What are your print settings?
mazas
mazas3mo ago
What about the heat from the bed? What temperature is it, and what is the chamber temperature? Is there a difference depending on the height the narrow part? And of course: what happens if you slow down the fan, does the issue get worse/improve?
Campapalooza
Campapalooza3mo ago
I ended up decreasing to 3 walls, increasing temp a little (215-220), enabled the orca setting to slow down on overhangs, and closed my enclosure doors (had them open) and so far that seems to be giving me better results. Thanks all!
MONSOONO
MONSOONO3mo ago
That will do it