Hello, I’m still fairly new to printing and I’ve been running into issues with Bambu Lab PETG Basic all day. First it was with some desiccant boxes — specifically the lids curling and getting pretty ugly edges. With some tuning I was able to get them to an acceptable place for what they were.
However, when printing my riser tonight, I went back to the stock Bambu PETG Basic profile and ran straight into the same type of issues again.
Does this look primarily like insufficient small-layer/overhang cooling, too much temperature/flow for these features, or possibly an issue with Bambu PETG Basic itself? Someone else printed this exact model successfully on a P2S using PETG-HF, and I’m trying to understand what changed.
PS- Is there any chance the Bambu PETG Basic profile in Studio is the old PETG?
Filament was dried in the AMS 2 Pro at 65°C for ~12 hours before printing.
These pics are from using 0.4 nozzle + 0.20 mm layer height + stock PETG Basic profile
I see quite a bit of stringing. Did you dry the filament before use? Bambu recommends drying before use. Fresh out of the package does equate to dry. PETG absorbs moisture quicker than PLA.
Once you have properly dried the filament, You should performa filament calibration for Pressure Advance (K value) and Flow Ratio.
I have to say up front I haven’t tried optimizing Bambu’s PETG Basic but even well-dried it doesn’t print stellar using the Bambu profile. PETG HF prints much better for me.
And I do know my filament is well-dried. I use a dry air purge during the dry and store in air-tight polyethylene containers with dry desiccant. After drying and cooling it pulls a hygrometer below 10% RH at room temperature with no desiccant in the humidity test.
My prints with it aren’t terrible but not the best either. It works but there can be minor issues especially for me with supports. The left part shows the bottom of the part where supports attached. The part on the right shows the upper surface of another part.
Unfortunately I don’t have any good advice for cleaning up prints using it. Your issues seem more pronounced so maybe higher water content - if any of the issues are due to water.
Yep — it was dried for ~12 hours at 65°C in the AMS 2 Pro before printing. I included that in the original post. I haven’t done PA/K-value and flow calibration on this spool yet though, so that’s something I can test next.
Thanks, that’s really helpful. That lines up pretty closely with what I’ve been seeing — the PETG Basic isn’t completely unusable, but the stock profile seems pretty unforgiving on supports/overhangs and small features. Mine was dried for ~12 hours at 65°C before printing, so while moisture may still be part of it, I’m starting to wonder if the profile/material combination itself is just not ideal for this kind of geometry.
Good to know PETG-HF has been noticeably better for you though. I may grab a spool and do an A/B test on one of the smaller failed vent pieces rather than reprinting the whole riser.
Also, I’m not entirely sure what I’m looking at in that photo but whatever it is, the print itself looks really nice!
It could just be a settings issue with something needing a tweak. Like I said, I haven’t optimized it at all so it could be my own operator error essentially.
And for the most part it prints ok even as is, but PETG HF was definitely better at least with the way Basic is printing for me now.
HF was discontinued though. I saw someone mention some was in stock in the US store so did a quick buy but it’s only white, black, red, and gray that were in stock when I bought.
Also, if you buy old stock and are new here, you might look into how filament was attached to spool hubs. Big topic a year ago. It was taped to varying degrees andj tape could get pulled through your filament tubes and glub up your extruder if things went especially wrong.
Thanks for the words about the model. Those are fittings from a free-standing greenhouse or frame for netting cover for a garden.
Update now that the print is finished:
I pulled the parts off the plate this morning and added a few photos. The inside of the vent section is significantly worse than it looked mid-print, and one outside vertical/corner section also has poor surface quality. However, some of the long exterior vertical walls on the exact same print came out quite clean.
Yeah I mean I have yet to see anyone say the “new” PETG Basic is great… Plenty about how the HF is amazing… But of course its discontinued, you shattered my hope with that one but thanks for the heads up ha.
But yeah I mean I tweaked for making the desiccant lids, which fixed some of the issues there but even that wasnt perfect… Hopefully theres something obvious that im just missing.
but whatever it is, the print itself looks really nice!
