What causes PLA webbing?

I am noticing my black PLA is webbing on my Taz 5. I am going with 195 nozzle and 60 on the bed. From the bottom to the top there is slight webbing which i don’t really see on ABS or HIPS.

Any suggestions?

Thanks in advance.

PLA from different brands, and different colors, may require to adjust temperature slightly. webbing is usually caused by too much heat, though 195 actually seems even a little low…

I was also getting a fair amount of webbing with PLA, and I think the default retraction settings in Lulzbot Cura are not sufficient (not pulling back far enough).

I’ve been playing around with creating Slic3r profiles - since the downloadable TAZ 5 profiles on the Lulzbot support website are for the .35 nozzle, not the .5, I’ve been trying to pull things together from a variety of sources/posts on this forum. I think I have a pretty good profile dialed in for PLA at medium quality (0.25 layer).

Key retraction settings were:
Retract Length = 1.5 mm
Retract lift = 0.1 mm
Retract Speed = 10 mm/s
Wipe checked (use wipe)

I found the 10 mm/s speed important since I would start to chew up my filament when I tried to retract faster.

I also cranked up my fan pretty high for PLA…

I attached my config bundle for slic3r - When printing PLA I use:

My tglase settings are in that bundle too, but they are still a work in progress (object centers are sagging) . As always, use someone else’s settings at your own risk… good luck!

use at your own risk.
Slic3r_config_bundle.ini (16.6 KB)

If you can only do 10mm/s for retraction, I bet your screws on the extruder are way too loose! Retraction speed is the most important factor to prevent stringing.
I’m using 55mm/s for retraction @1mm. More makes no sense because the acceleration is limiting speed on the short move. But this may not work for you, 55mm/s for unretract may lead to blobs. I’m using Marlins FW retract where I can limit the unretract speed in another option.

In addition to the retractin, the strings are a sign that the extrusion temps are too high for the filament. Lower by 1-3C…

Thanks for the tip - I’ll keep working with it.