Hi,
Can anyone point me to what is causing this issue?
I’ve never had this issue before and it’s happening on the same spot even on different types of filament PLA and PETG.
My filaments were dried and still having the same issue.
Check nozzle to see if it’s bent.
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You might need model supports, bad overhangs could cause that
I put in the replacement nozzle same thing.
I’ve also calibrated my filament.
Not sure what to do anymore.
It looks like your PA calibration is way off.
And/or you are pushing flow too much. A slicer preview would show if that is in a flow controlled region.
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Run the print at “Silent” speed (slowest) and see if that makes a difference.
This looks like a flow issue, but if you’ve run calibrations on multiple filaments and gotten basically the exact same results, unless you’re making the same mistake each time you calibrate (and maybe not even then) I don’t see it as a plausible explanation.
And the rest of the print looks pretty good/clean. So it’s probably not a flow issue.
Same logic applies to temperature.
What are the flow and PA and temperature settings for this last print? What filament type?
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What are your support settings? It looks like it is generating supports out beyond the model. You most likely do not need to change any of the individual values. Just enable supports and leave all the default settings as is. The base of the supports will be beyond the model but some of the very outer supports seem like they should not even be there.
Can you post a link to model?
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Many thanks for these. It does help, but there are still many possible root causes that spring to mind.
While the error pic’s suggest a flow or PA issue, the slicer previews do not back up the flow limit root cause as areas with a higher flow above the error region do not show the defect.
So it is quite a bit more complex. And, unfortunately, neccesitates a few more questions:
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Is the error side facing the Aux-fan (if you have one)? Or the front left corner or the poop chute and quite close? Drafts can also cause these types of defects but can usually be influenced by re-positioning on the build plate or other means (reduce Aux-fan, etc.). I regard this as unlikely though as errors would have varied between PLA and PETG.
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In which direction is the print head moving in the error region? Is it in this direction? If yes, PA could still be a reason, but probably not the only one (see below).
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I agree that more supports than neccessary are generated. It may be worth enabling “remove small overhangs” in the support settings. But again, that is probably not the (only) root cause. Best to stick to the defaults for now.
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What is noticeable from the layer time preview is that we have increased layer times for the defective layers. It would be good to better understand what is happening here using the 3mf. It may be related to time taken for further geometric features hidden in the pics or from the “slow down for overhangs”.
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Speaking of “slow down for overhangs”: Do you get the same defects if you set all overhang speeds to 50mm/s using PLA? That was successful in a recent, similar troubleshooting. It can only help if the tool head movement is in the direction I indicated above though.
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It is always a good idea to troubleshoot at reduced speeds. Not only because it removes important root causes, but also because it is easier to observe and listen. I did have issues in the past with “slow down for overhangs” where the fan’s were coupled in the filament settings… but taking some time to speed up, thereby over-cooling in the wrong positions. There’s now an option to add that in the filament settings (but 0s by default).
There’s still more, but I think once we go there, we really need the 3mf. And best to stick to well dried and calibrated (also Pressure Advance!) PLA for now. All that curling/warping related stuff with PETG is something to be dealt with once the print works in PLA.
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Run a full printer calibration
Test.3mf (7.1 MB)
Uploaded the 3mf file.
Weird things is I printed this on .2 layer height no issues but when I do.08 it happens.
I’ve also rotated the model and printed it in all directions the issue still occurs. (on .08 layer height)
Support settings was set to default Tree auto I’ve also tried manual and painted them same thing.
Did the silent (50%) speed same thing.
My vote is +1 on pressure advance being a part of the problem
I’ve found when printing at ultra small layer heights (0.08 in your example) that retraction needs some tuning from normal. My profile+filament permutation found that reducing the retraction length from default (0.8) to about half (0.5) helped keep those “surface tears” from appearing, but you should run a test print instead of taking my values as fact.
Also, try to paint your seam as far away from retractions and overhangs as possible, if you are able. If this helps, it is an even bigger indicator to also do some pressure advance calibrations.
One more thing - rotate the model 90 or 180degrees on your bed, and rerun. This can help tease out mechanical/cooling/nozzle issues vs model/profile issues
Here is what I get when I slice your model.
I have put a brim around the outside ONLY. I have an item I print that is very similar in size and shape, smaller though. My brim thought process being that the circular portion has very little contact with the build plate.
Of note with the supports is you have a threshold of 15 set which I ran with. Recently the default has been 30. I believe in the past it was some other value. Is your firmware current? I know some folks have had issues with firmware and so have rolled back to older versions.
Printer 01.05.02.00
AMS 00.01.06.62
AMS 2 Pro 02.00.19.68
Brim setting
Supports
Speed
I’ve tried and test all the above comments.
I painted the seam at the back
change the retraction
rotated the model
slowed down the print
I still get the same flaws in the print.
I’ll try down grading my firmware ( I was running the latest FW)
I also did this calibration
I have not had a chance to look at your 3mf yet but we can already conclude a few things:
- PA/Flow Dynamics is calibrated
- Defects are layer height dependant (Thanks for that additional info. Are the prior previews from the 0.2mm or the 0.08mm slice?)
- Defects are likely independent of rotation on the build plate (The above pic of the part on the plate actually indicates the opposite, with the defects facing the Aux-fan. However, you mentioned you had rotated it).
- Defects occur away from the seams in long layer time heights only. They occur after major overhangs (speculation on my part as I did not spot a response to my print head movement direction question).
=> Defects may occur due to rapid acceleration after “slow down for overhangs” where in low flow conditions high sensitivities must be expected.
=> I’d recommend changing all “slow down for overhang” speeds to 50mm/s for a trial. This reduces inconsistencies in rapid flow increases while (for PLA) still giving good overhang performance.
=> I’d also advise to lower outer wall acceleration to 500 mm/s (maybe using a local modifier) for a further trial if errors persist.
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Take your pictures of the failure with the models still on the build plate.
The build plate is part of the process. You are scrubbing the build plate routinely with a strong soap?