Hi, could you guys please help me figure this out - I was halfway through a print with BL translucent PETG and noticed that there started to be strands running up from the build layer and my nozzle was scraping against those artifacts. The infill setting is 15% rectilinear.
What could be wrong here? I have dried the PETG to the recommended 12hrs in 65C with the AMS 2 pro, and I have done calibration and bed leveling before the print.
I read that having grid infill may cause running the nozzle against the infill, but for this print it is rectilinear, does that cause the same issue? If not, what can I do?
Thank you in advance!
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Yes, crossing infills and surfaces are a problem with PETG. Choose non crossing infill (honeycomb, gyroid) and surfaces (monotonic, concentric).
I have also made good experiences with “wipe on retract” enabled.
PETG also rewards going slow but I may be too conservative on this count.
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Thank you, I’ll dry my petg again and try gyroid, also try the wipe on retract settings
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For PETG, I have switched from Gyroid to Crosshatch, which prints quite a bit faster with no real downsides. Just mention it for completeness. For avoiding that scraping issue, both should be equally fine.
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Rectilinear isn’t an intersecting infill pattern. It crosses the previous layer just like gyroid, on the next layer.
OP, slow your infill speed down to 80mm/s and disable reduce infill retraction.
Rectilinear is my go to infill and all I print is PETG & PET. The only time I get this issue is when I try to print too fast or the flow rate isn’t calibrated properly.
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Oh, very true. Sorry for not reading carefully.
I think the change of direction in every layer is more prone to buildup like this compared to gyroid or crosshatch, but the root problem probably is somewhere else.
I have used Bambu translucent PETG for the first time a few weeks ago and I found it very picky compared to PETG HF and most PETGs from other brands. The experience was really underwhelming. It was my first roll and will stay my last.
@Qjo probably has nailed it with the advice. You could incrementally increase speed to find the limit. Or you just accept the longer print time.
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Thank you all for the great suggestions! I will try them and update how it goes