Right now I’m running a print that has failed overhangs in some places, but in other places (with the exact same feature) its failing? I’ve tried on both a P1S and H2D with the same outcome, so I know it has something to do with the settings. I’ve slowed everything right down for speed and accel, and using default filament profile with calibrated K values.
With or without supports?
Slicer preview → Check if the seam is very near the failing overhang. If so, relocate it.
Slicer preview → Check fan speed + print speed for the area that is bad, and the area that is good. Did they receive the same cooling treatment?
Prepare model → Measure → Is the angle of those slopes the exact same? Informative only.
If unexplainable still, bump fan on overhang to 100%, consider slowing down overhangs even more, and reducing nozzle temp in slight increments until it behaves.
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Legendary reply, thank you!
I’ve tried the seam preview, and speed/fan preview with no differences or seams to report. Also the model is mirrored left and right so I know the angles are identical.
I hate the idea that I have to mess with the default filament profiles so I’ll try playing with speed settings even more so and report back here. Thanks!
Additionally, with my P1S, I noticed that the area on the front left seemed to have different cooling properties [when i was testing ASA]. I taped the door’s hinge-side closed with some painters tape, and printed a “vented riser” to make all the heat entropy drama happen up at the top and via the machine’s fans, and remove from the equation that little slit of air… I’m not sure it helped in my scenario since I moved on from that filament + model, but I felt like I did something productive.
your mileage may vary
Do you notice how the 90 degree corner on the first pic also looks bulged, like it was an out-of-spec pressure advance at that flow/accel. I don’t have a good theory for how thats possible on the same part with crisp PA-looking lines on the other side.
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Without just because its a 50 degree angle. Should be more than able to handle that in my experience.
Anything that causes issue on only one side is usually a calibration issue.
I would check your nozzle and ensure it and the rest of the hot end aren’t loose and there isn’t anything blocking the flow or otherwise snagging the print a little.
Make sure everything is clean, balanced and no belts are slipping or otherwise loose.
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I’d try using supports rather than fighting to get it to work without. That might take hours
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I hate the idea that I have to mess with the default filament profiles
Sadly you have to. Filament manufactures are not the wizards (even Bambu Lab themselves), they can’t predict the ideal settings for every P1S or H2D printer. There are so much factors that may change your print quality.
The supports mostly destroy the print quality. You should use them in extreme cases.
I use supports all the time with no impact to print quality. An overhang like that I would have certainly used supports and the result would have been significantly better.
Your machine to do with as you please but I would ask how long that print took to result in a failure and what is your goal. Is it to generate a print or to generate a print without using supports? Personally I think BL has done a very good job with the programming around support structures and maybe try the print with support before discounting supports across the board.
3D Printing Supports – The Ultimate Guide
This is the proof of not enough cooling because of layer time is too short. The matter becomes worse with seam located there.
You should design the part to avoid support, yes! But support is not that bad as you think.
I think you should start tuning some parameters.
E.g. Smooth coefficient
[Bambu Studio advanced quality settings | Bambu Lab Wiki](https://Smooth coefficient)