What causes this on PLA? Too little cooling? Or possibly too much??
Anyone have any idea what might cause this sort of issue on PLA? I run into it frequently, but pretty much 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
This is from a printer with a 4028 fan (i.e. pretty massive airflow, server type fan) so even the 35-45% (based on layer time) I have it currently set at is more than 100% with single/dual 5015's or etc.
I guess my other option is to try supports, but this doesn't really seem like a situation where supports should be needed. Anyone ever had a similar problem and solved it without just turning the speed waaaayyyyyy down?
I'm seeing quite a few strings there around the nozzle and fan ducts. Another thing that can cause that curling is wet filament, which will also cause the stringing. So you might also try drying it.
Good question! I probably could try drying this filament again, just for kicks...I did dry it not too long ago but it's probably been long enough that it couldn't hurt. But yes I've seen this issue with virtually every PLA filament I've used when the factors I mentioned are all true.
When this failure occurred, I was about 100 filament swaps in (it's a multicolor print) so faint evidence of the nozzle purging/eject/reload/etc process in the midst of powerful fans is at least initially what I had attributed that to.