Generally, I don’t have any major quality issues when printing PETG, but this model is giving me a hard time. I reduced the extrusion rate from 0.95 to 0.93 and recalibrated the filament.
I suspect that trying to print a lattice structure without any supports is part of the problem, since the rapid movements between each section must be causing the object to shift.
If that were the only issue, it wouldn’t be so bad, but you’ll notice that some of the overhangs look terrible. What do you suggest?
These structures are torture tests for the basic profiles. Honestly, depending on how critical you are on the quality, no base profile is gonna be good enough.
Things you can do to improve performance…. ensure dry filament, slow down print speeds, and re-tune the retraction. Pressure advance and flow settings could help, but should be insignificant. Pressure advance is for acceleration and deceleration print defects. While there is acceleration and deceleration in this structure its not the type that the setting was made to improve (designed for rounding a corner while extruding, going from high speed movement to low speed then back to high speed).
Also, I just noticed your biggest problem is on the overhangs. The mesh is what I was speaking about above. The defects in the overhangs are cooling defects.
Two things to start off with to fix that, slow down the print speeds and increase the fan speeds. It looks like you are just barely over the limit because the similar features earlier in the model printed better. So something like 10-20% more fan or 20% less speed on overhangs may be good enough.
I suggest you break the print up into one per flat part of the box, build interlocking sides (like laced fingers) with a hole through all the fingers for a piece of fillament to be inserted to lock them together. Then print each side laying flat.
It would be faster, stronger, and not have the same print artifacts.
