Having printed successfully with PLA for a few weeks, I’ve bought some basic PETG from Bambu, and am immediately having problems. Here is an example on the SuperTack plate:
The two squares are swatches - the black has printed quite well, albeit with deformities on the little S-shaped gap, but the white has lifted from the bed and has more artifacts on top. (A previous attempt at the white had it come fully off the bed and make a big mess while stuck to the nozzle.) The other black shape is a clip which seems to consistently fail; I cancelled the print before trying a white clip.
I suppose the models are not adhering to the plate, but I’ve not had that problem at all on the SuperTack plate with PLA. I did have that with the standard textured plate after many prints, but washing the plate and cleaning with IPA resolved it. I’ve tried the PETG on both plates and neither works - the black swatch on the SuperTack is the best I’ve had.
Filament settings are loaded by Bambu Studio for the Bambu PETG Basic preset: 255°C nozzle, 70°C bed. The PETG has come straight out of a sealed bag direct from Bambu so I’d be surprised if it had the wrong amount of moisture at this stage.
Are there other settings I should share, or other things to try? Thanks in advance!
Prepare to be surprised. Filament should never be considered dry from the packaging. It isn’t dried before packaging, it’s actually run through a water bath when it’s manufactured.
I’ve found cleaning with IPA cause adhesion problems. I stick to Dawn and hot water now.
Pretty sure Bambu says it has to be dried before using. I am not saying this is what your problem is.
I agree using IPA only to clean it is possible to just push the oil around and then the IPA evaporates and the oil is left. When using IPA to clean a part I use a spray bottle and flood the part so the IPA rinses the part of.
These are the tips I need to learn how to incorporate into my printing. When you start and only use the app you don’t even realise these things are an option… thanks
I won’t beat around the bush. the printer should remain sealed in a room throughout the entire process. If someone opens the door, the draft ruins the print. If someone walks past it, the air movement ruins the print. When checking the bed during printing, you must hold your breath the entire time
With a clean plate and dry filament, you should be able to print without issue on the A1 without a “sealed room”. Lifting and warping of PLA or PETG like you show is almost certainly not due to drafts.
The Bambu default plate is “braindead easy” for printing PLA and PETG, to the point where you may have too much adhesion with PETG at Bambu’s recommended bed temperatures.
A nylon scrub brush dedicated to cleaning your plates and Dawn or Palmolive Pure and Clear dish detergent, preferably unscented and definitely without “gentle on hands” ingredients, are generally the way to go.
Same here. Even cleaning is non-critical especially with some glue. I mostly print on textured and smooth PEI with PLA and PETG HF, and a bit of Bambu liquid glue keeps things stuck down and then separates easily without stress marks. No problems with drafts or the door open. I might be wrong, but dry filament seems to be the secret sauce.
Looking through these comments, the common suggestions seem to be to dry the filament, and to clean the plate.
In both cases I’d like to ask: is there expected to be a difference between PLA and PETG? Both of the plates I’m using have been fine for PLA (and as I said, when one wasn’t fine I cleaned it and it went back to being fine again) - does PETG have more difficulty adhering to a plate than PLA? It’s hard to know if the cleaning I’ve done is good enough; I’d hoped that if it was good enough for PLA, it would be good enough for PETG as well.
Can I dry filament easily with items I already have in the house, or do I need to buy a dryer? I don’t think it’s particularly moist in the air where I live (again based on having no PLA problems), but I don’t have a way to measure it; it’d be nice to avoid spending money if it turned out not to be the problem.
The word “dawn” has been mentioned which I gather is a brand of soap. Is there a specific ingredient to look for? It’s not something I’ve come across in the UK so I’d have to look for another brand with the same properties. (I’ve tried some supermarket own-brand dish soap - it worked once, but the second time it didn’t make a difference so I had to use the IPA.)
According to the datasheets, PETG actually has a lower Saturated Water Absorption Rate than PLA. However, PETG does react much more drastically to moisture than PLA. Adhesion, Oozing, Stringing, Warping, Curling,…
Furthermore, keep in mind that PETG is frequently used as an interface material for PLA due to the materials incompatibility. They really do not like to bond. So if there’s PLA residue or dust on the plate, even the usually very sticky PETG can get into trouble.
Dawn is a popular US dish detergent. The key past excellent grease cutting ability and clean rinsing is no additives to make it “easy on hands’“ as those are often oils or oily additives of various sorts.
You can dry in a conventional oven or toaster oven, but you need to watch the temperature carefully. Most cooking ovens aren’t very stable for temperature. If you can print straight out of the dryer through PTFE tubing, that is an advantage. TPU, for example, can easily absorb enough water sitting out during a long print t cause problems.
Here is one reviewer of various dryer options
I personally use a Creality SpacePi x4. If you’re sticking with PLA, PETG, PCTG, and TPU, you don’t need quite as high a temperature as that supplies. For any of those other than PLA you definitely need a dryer.
Edit:
You will also need desiccant. The silica beads are acceptable. If you can avoid the blue indicating ones (somewhat poisonous) and stick with the orange-to-green ones, that is an advantage. Packets can be regenerated in a cooking oven at moderate heat. Activated alumina (“3A molecular sieve”) is better at very low humidity, but requires much higher temperatures to regenerate.
Just a quick note: Activated alumina and molecular sieve are not the same. Activated alumina does not draw moisture as aggressively as molecular sieve, but it only needs 150-200°C instead of 250-350 °C like molecular sieve for regenerating.
Update: I cleaned and re-cleaned the plates, with dish soap (again) and IPA (again), and finally the prints stayed still. I did then get a new issue with a wide PETG print that started lifting from the sides towards the end of the print, but I’ll start a new thread if that continues being a problem. Thanks all!
This is my dry cabinet. Bought it on Alibaba (could not find anything this dimension in US) $1000 to my door. I have it set to 15% RH and it can go lower (66 rolls in it so far). I also use Hygrometers in my AMS units. I don’t trust the Printers guess at RH. I also raise the bed temp form the default 70 degree C to 71 or 72 using eSun PETG and PTEG-HF. I’ve tried other brands that I had to throw out. It’s too bad that BL has almost to PETG selection. I’m not advocating anything here, just passing along what works for me.
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