i got some ugly blobs on my prints with overhangs. but strangely not on all layers, the bottom 20 seem to be very OK. it’s not bed adhesion as the top surface is perfect, so no moved part. my P1P is enclosed and i print eSUN PETG. i fine tuned the printer for 2 weeks now, initially because i had ripply outer walls (probably resonance from printing around 120mm/s). could this be from part cooling? but if then, why is the first gear perfect. i printed it with slightly modified standard settings. all settings in the images attached. does anybody have the same problem with the blobs, before I spend another half kg filament and some evenings…? thanks for any advice!
linear advance is set to 0.030. calibrated for 0.085 but then i had underextrusion in edges.
I would think it is connected to part cooling and P1P environment. Also it is possible that the bed influences the part cooling due to the proximity to the plate and the heat source. In close examination it almost looks like the top of the first part failed. It also looks like the issue continues to get worse as you go up. Like the environment is too cold.
I would adjust the cooling or the bed temperature. I would think you only need to get the second gear to be good, so the test would be able to terminate just past the first gear.
thanks a lot for the detailed reply. this could be the problem. currently I am calibrating every filament type again for pressure advance, temperature and flow. I will then try again with the new settings. and it seems that somehow “slow down for overhangs” was not checked in all my settings. this is for sure not helping this situation…
wow ok. I don’t know how this happened. I checked all my settings, and on all profiles it’s disabled. very strange. I will try the print again when i finish the calibration for the filaments. thanks a lot for the hint!
Did you figure out what the problem was? I am also having overhang issues and it all happened as soon as I added the AMS and updated the printer. Overhang wen to ■■■■ and now I get blobs that I was not getting before its bad
not yet… i calibrated all filaments for dynamic flow and pressure advance with orcaslicer and did all settings from scratch. i have another model (ABS+) with similar issues. here i can clearly see that the layers are warping up which causes the blobs. maybe i need to print even slower or disable cooling at all
I was having similar issues, until I installed the auxiliary fan, perfect prints afterwards. See that the blobs appear on a steep curve and not on straight lines (think of the printer head movement), that means that the centrifugal forces eject some hot filament outwards because it is not quickly cooled down.
Definitely “Slow down for overhangs” (I have 0,40, 20,10) but you also want to increase the fan speeds for PETG. The big one for your print here is the Overhang fan speed. I also turn on the Aux fan to 20% and also leave the chamber door open but not sure how important those are.
Note: Very different for ABS/ASA filaments where you want little to no cooling except for the overhangs.
thanks for any advice!
