Hey,
with the newest Firmware i got the 4th failed Print like this of 10.
Any Idea, why this Problem is coming?
Thanks
Did it just spontaneously print that defect during the print or did anything happen like a spool change? Did anything else happen around the time the defect printed? Do all the failed prints look exactly the same as that one or does the defect appear in different places each time?
That happened during the print with a single spool (no change). I couldn’t notice anything unusual. I’m currently printing a tower for testing, and at the current height, everything looks good.
The error occurred each time at a height of around layer 470±10.
Here i paused the Tower:
If this happened once or multiple times, but, at different points, I would suggest the filament spool had areas of jamming that spontaneously freed themselves with sufficient pressure.
Four times in the same place doesn’t sound like that though as the error is too uniform.
If you are printing from an AMS, swap the slot your filament is in.
Either way, use a different filament spool.
The idea is to rule out things.
That’s a lot of filament to do trial and error printing. It looks like a shrinkage problem. There’s a gap then plainly seen “printing over air” filament. The gap seems larger on the opposite side. Perhaps caused by a fan or open door.
Need more specifics on the print. (Nice model though.) 
Edit: Forgot to ask, what’s the tower for? It looks really close to the same height as the break. Filament changes produce cooling and induce shrinkage.
My best guess from looking carefully at your photos is that the part is coming partially away from the bed when the printing extends horizontally away from the base center, due to printing forces and leverage issues. You may not be able to see this taking place as the part is likely see-sawing back into place as the print head moves to the other side again. Once the width of the print returns closer to the center, the leverages in the printing forces reduce enough to allow the part so sit still again.
My theory is further supported by the base of the part having very low surface area for build plate adhesion — it’s a circle with a thin circumference.
If I am correct, adding a brim to your print (in the Others section) with a width of 5mm and a spacing of 0.1 or 0.2mm will help a great deal.
Additionally, if you have successfully printed this part six out of ten times, it suggests that the print sometimes comes partially unstuck, depending on your luck with it being only marginally able to “hang on.”
Either way, my experience tells me that such a print profile would absolutely need a brim to be reliable.
Hope that’s it! 
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I bet Gruvin nailed it. Makes sense and accounts for the issues happening at about but not exactly the same place. The firmware update probably had only a slight effect but enough extra drag on the print to start breaking it loose, maybe?
And as Ken noticed, the purge tower is odd to be there and a different color? I’m guessing it’s from a different print but looks like just one color. Not really necessary when printing a single color and could contribute to defects by having the print head leave the model each layer to go print a layer on the tower - if it is associated with this print somehow.
Ah - the tower was just a test to see if it failed at the same height and I bet it didn’t. Even though tall and narrow, the base of towers usually get a brim (don’t see one on yours) but still it probably has a solid base printed on the bottom and might even have more contact area.
If it is breaking loose, as Gruvin said a brim could help. Maybe even glue stick or other technique to help it hold down if you can’t print a brim for some reason.
The print model was still very firmly attached to the print bed, and I had to bend the print plate quite a bit to get it off. I always use glue for that, and it holds very firmly.
Even with a brim, I had this problem with the new firmware. Meanwhile, some prints with even less surface area work without any issues. Based on my experience so far, it doesn’t seem to be an adhesion problem.
I’ve now set up a small video server that continuously records the prints, and I might soon get a video that explains this printing pattern to me.
Hmmm. Well that settles that then.
Looks like we’re in the realms of needing BambuLab to analyse the situation.
In the meantime, on the basis that it may be some obscure bug in the slicer producing something the printer gets confused with in the GCODE, you might try simply rotating the part a little (or a lot) and just see if that kind of randomly gets around it, for now.
It would be nice to be able to downgrade firmware to a previous version to confirm or rule out if the update is in fact the cause.
Cool! 
Are you able to post the GCODE file for us to analyse? Even just the code relating to plus / minus 30 or so layers from where the fault generally occurs — I mean, should the overall part be something something you wish to keep private.
The curvature made sense with what Gruvin said but with that being stuck down solid I have no other ideas. I hope you are able to get it sorted.
I completely reset the printer yesterday and recalibrated it. Since then, I have printed this component 20 times without any errors. I will monitor this for a week and report back if the issue recurs.
Unfortunately, I do not have a Gcode for this. I always send it directly to the printer, and it is the Hydroponic Tower.
Thanks
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As my dear departed grandmother said, “If you’re going to have one have a big one.”
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Well far out eh! That’s good news, if not surprising and tad interesting to boot!
Ironically, you have reminded me that I was considering printing hydroponic towers — maybe even the same one — last Spring. (It’s winter here right now.)
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