Using a new A1 without AMS lite just got it 7 days ago.
Printing with Inland PLA+ and got burning smells at some point whenever it prints. When I started at first there were none for the first 2-3 days. As soon as the plastic starts flowing/shooting out I can smell it. If I pause it I can tell no more smell is being generated until I start again. When it poops filament what comes out if I grab it has the burning smell, but not so much what it ends up printing despite it smelling the entire time its doing that except when I pause.
At some point I swapped to a Inland PETG and the smell stopped. But I was getting bad printing issues that I’m still trying to diagnosis. I was getting lots of bits of plastic thrown about and printing looking all messed up from the area it came from. Figured out plastic was sticking to the nozzle and causing this. If I actively watch it and keep brushing it off when it starts to stick I can get a decent print. Multiple times I’ve done all the calibrations you can do the full long one including the bed leveling shaking and all that stuff that takes like 30 minutes, and just the Flow dynamics one that you can choose before printing. I make sure to have that flow one always done after I change something. None of that has helped. I also ended up drying the Inland PETG for 8 hours and that didn’t help.
Then I switched to eSun PETG HS (also dried for 8 hours) which right away started the smell again as soon as it started extruding a bit. Using a filament profile for the a1 for it that I found on the eSUN site, its only a bit different than the generic HF one but does have more reasonable fan speeds that are slower. So messed with Gyroid infill and turned off reduce retraction based upon comments here to try to improve the print quality. Made no difference. I’ve been printing a scraper over and over again with all my tests just because it fails badly with that especially when filling the blade part.
I just lowered the the max temp from 270 to 260, the first layer temp from 270 to 260, and the inner layers from 270 to 250, and it came out slightly better, but smell problem persists and still printing unacceptably bad and still sticking to the nozzle several times during a print. And when I pause a print it almost always strings when moving the print head to the left (which it also did at higher temps).
Also other problems. Every time I’ve changed filament it ends up not working right. It will not be able to find the filament despite pushing it in as best as I can, and each time that happens I’ve ended up eventually trying to pull it out, and it feels fairly stuck as if its where it should be, but can come out with a bit more force. One time I got it to work by just doing retry over and over again and eventually pulling it a bit out and then putting it back in. About 3 times now that failed and I ended up having to remove the hotend while hot and pull out the filament from the top of the hotend. Then putting it back in finally would get it to pull the new filament in. The smell I think started after the first time I did that perhaps. Also messed with the built in profiles like Generic PETG, Generic PETG HS, and Bambu PETG etc… and there is no noticeable difference in what happens with them.
Any help on any of these issues especially the smells and print getting covered with small bits which end up eventually messing up the whole thing when there are enough of them?
Not having an A-series, I need to limit my response to my experiences with PETG.
- I have found it neccessary to dry all PETG when coming out of the bag. The filament has crossed more Oceans than I have by the time it gets to me.
- Similarly, I have found PETG responding very well to slower printing speeds (<100mm/s for Basic, maybe 120 for HF),
- accelerations (25% of defaults) and
- layer heights using adaptive layers (reduced heat input per layer => more even cooldown => less curling) while strongly favoring
- non-crossing surfaces (monotonic, monotonic line) and infill (honeycomb).
Regarding the trouble changing filament and the smell, that is a bit of a puzzler. At what temps are you printing the PLA?
And a final thought, there have been reports of the A series occasionally suffering from print problems due to screws being loose in the tool head. That is a bit of a long shot, but very difficult to diagnose while being easy to check and correct.
When I printed PLA it was just Generic PLA profile with no changes at all. I see that is set to 240 max, but both the first layer and the others are set to 220.
Is Gyroid also non-crossing too? I had found a comment saying it and honeycomb were not, so switched to Gyroid but have not tried honeycomb yet. Going to try that surfaces stuff and honeycomb, and the screw stuff though.
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220 sounds good. So still a bit of a puzzler as to the smell. That should not happen wirh PLA. Is it just one roll or all?
Both Gyroid and Honeycomb are non-crossing. I personally just prefer honeycomb over gyroid as I find honeycomb printing a bit cleaner due to the intermittend dual line width and lack of bridging lengths. It needs a bit more filament though.
PETG tends to retain heat very well which is why it prints more accurately when going slower. Acceleration reductions do the same for small features as the print head needs 2mm to reach its top speed if not kept in check.
The other thing where PETG differs from PLA is that it loves to stick when molten. In particular to the nozzle. That is why it is important to avoid speed bumps with PETG.
Since you said the smell changed/went away when you tried another brand, it might just be that brand of filament.
Myself, I think PLA smells sweet, like syrup…some people can’t smell it…JMO
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Makes sense, I may need to get another roll of the first one I used just to double check – it bothers me enough that I will purposely keep track of which smell and don’t so I can buy the non-smelling ones. I still have another roll of another one that didn’t smell, but I tried to switch to it just to double check and the extruder is definitely clogged or messed up it won’t feed the filament and I measured it to make sure it wasn’t too thick. Going to have to open it tomorrow to check what is going on.
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Very strange I took it apart to see what was stopping me from putting filament through and there is no visible cause, I tested the entire filament path taken apart and couldn’t find something to cause it. Only thing I found of note was this tiny crack here, but it doesn’t seem like that should cause any issues.
Also a few little black specs inside the extruder that seemed way too small to cause an issue, but we will see when I put it back together now that they are cleaned out. Going to contact bambu directly if after I put it back together I still can’t get it to feed in the filament in.
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Submitted a ticket to them just now. Twice more if took several tries for it to get the filament when I swapped to a new one.
Got eSUN PLA Basic Filament gray for $12 on amazon currently and it seems to print well and smell less than the others, it can do high speed so it’s a really great deal for just one roll.
Got Slice Engineering Plastic Repellent to paint on the nozzle tip to see if it will fix the PETG issues, I didn’t have as many issues with it when I first tried it as I do now and didn’t need crazy tweaks to get it working maybe it will help.
