I’ve just ordered my first lot of Bambu PLA Matt filament and am having an interesting time with it! It seems to print differently to regular Bambu PLA Basic which I’ve been using largely without issue.
I’m attempting to print a self-watering plant pot from makerworld, however I cannot seem to stop it warping and producing a ridge on the outside of the model where the infill/top surface of the bottom of the model finishes. I believe this is shrinkage but in two different ways.
So far I’ve tried aux fan off, print outer walls first, adding a brim, changing wall generator to Arachne and upping the bed and nozzle temp a smidge. Filament was dried for 12 hours when it arrived and is being used in the AMS with the standard 0.4mm nozzle. Bed is the Bambu textured PEI sheet that was thoroughly cleaned. I used the automatic calibration for the flow rate on this filament before starting too.
Just as a test, I cut a small section out to test print so I’m not wasting so much filament each time and with the PLA Matt, while it didn’t show shrinkage where the infill/top surface of the bottom of the model finishes, it did warp still. I printed the same thing with regular Bambu PLA Basic and that printed without any warping or shrinkage.
Can anyone offer any advice on what else I can try here? I’ve attached a photo that shows the warping at the bottom and the ridge around the edge
Well… since nobody has yet to respond to your question, I’ll see if I can help.
It would be helpful to show a screengrab of the sliced model as it sits on your plate. This may be the reason you haven’t gotten any responses yet because a photo could mean a lot of things, what is not known is what the model looked like before it was sent to the printer. If you can upload a screenshot of the sliced model and/or upload the 3MF file, it would take a lot of guesswork out of this answer.
But in the absence of that, I’ll try to guess as to what’s going on here.
I see two issues in the photo you uploaded:
Model lifting off the plate
This can be resolved by cleaning the plate properly.
Or using Glue
Or increasing the build plate temperature.
Layer transition which is generally caused by changes in the material density of the model. Again, uploading the 3MF or at least showing the cross-section of the model would take the guesswork out. The remedy for that can be a number of possible solutions which I’ll try to explain in images below.
It may be helpful to understand why these lines appear at the edge. Assuming your model was not designed by you but downloaded off the web, I’d guess that the designer just did a simple round dish and did not take into account that the more material that is extruded, the greater the shrinkage after it exits the nozzle.
Two potential remedies to remediate the transition line
The ideal remedy is to add a fillet to the model which makes the transition less abrupt. That would look like this in CAD.
Assuming you don’t have access to the original model, the second remedy is much more complicated as it involves trial and error with slicer settings.
What follows are the settings you can adjust that will have an affect. It’s important to attempt these one at a time not in combination right away, so that you can best determine which one has the most affect.
Option A: Increase the number of bottom layers to a height that is larger than the bottom of the model. This will cause the transition between the bottom to the side walls to be less drastic.
Option B: Do the inverse and increase the wall layers so that you have solid walls. You can use the the height range modifier option to restrict the change in wall layers by height. Here’s where that is found. [Click through gallery for zoomed-in view]
Option C: You can also experiment with changing fan speeds in the filament settings to ensure that it is all-on or all off for the layers that make up the bottom of the shell. I’d doubt that would be effective but it is worth a try.
Option D: Change the wall order to outer/inner from the default of inner/outer. This will cause the outer wall to be extruded first and might give the model time to set up properly before the next pass.
Option E: Change the speed setting to “Silent Mode” after printing begins. This is a one-click method that will slow down “all” nozzle movements by 50% but you pay for this in print time.
Alternatively, you can go into the speed settings in the global slicer and change the outer wall to half the speed it’s set to now. The advantage to that is it only slows the wall speed down, not the entire model. You’ll see the difference in the slicer estimated print times.
If any of these or other remedies work, please return the favor by telling the community what worked for you so that others can benefit.
