Problem with Prusament PETG
I've been printing big objects with sparse (5%) cubic infill (they're moulds for moulding carbon fibre parts on) with my Prusa XL with enclosure. These have been working very well with standard ColorFabb economy PETG. I recently got some 2kg rolls of Prusament PETG (they were on offer and I was ordering other items from Prusa, so it seemed worth it, and I thought it would work better than the economy stuff). However I'm now getting bad defects on the infill. These start as little gaps, but get steadily worse as the print progresses, eventually the infill is so messed up that I have to cancel the print. The perimeters seem to continue to be OK. I'm using the same gcode files I sliced for the economy PETG, using the "Prusa PETG" preset in PrusaSlicer. What's going on here?
RE: Problem with Prusament PETG
P.S. First mm are OK, the problems start after quite a bit of height (maybe more than 20-30mm) has been printed, and get worse as it gets higher.
RE: Problem with Prusament PETG
Underextrusion. You can see by the matte sheen on those areas that your barely extruding enough material. That dull matte sheen comes from not getting hot enough in the nozzle. Try raising the nozzle temp at least 10 degrees, or slow down the infill speed.
Another alternate option is to reduce the volumetric flow rate in the filament profile.
Out of curiosity did you use the Prusament filament profile?
RE: Problem with Prusament PETG
No, I was using the "Prusa PETG" profile. Looking through them I see the the "Prusament PETG" is 10 degrees hotter than either the "Prusa PETG" or "Generic PETG" profiles (240 first layer, 250 all others for Prusament, 230 first/240 others for both the other profiles) . I've raised the nozzle temperature 10 degrees and am trying again, so far it's looking much better. So it seems that Prusament PETG has a higher melting point than other PETG's.