Hi! Long time reader but it’s my first post! I tried to look for solutions but none seems to be working for me.
Issue is, when I print “tall” objects, nozzle seems to do noises and scratch the outer layer. My issue now is not with the infill (But has happens other times), but with the outer wall.
I’m using Bambu Lab A1,filament used: It shouldn’t matter because same things happens with other filaments but PLA RECYCLED Light Green from SmartMaterials3D.
Here are my settings:
Let me show one piece that can demostrate my issue clear:
This is the piece I am printing, in that left vertical wall you can see the damage the nozzle is doing:
But the other side seems ok:
This happens with other printings, sometimes not that serious and pieces are usable (but not perfect) while other times, like in this example, are unusable and I have to stop the print.
Any help? Thanks a lot!
Hi,
Hard to tell for sure from the photos, but could the print be warping, not staying flat on the plate while printing? That box shape in particular would typically be prone to warp. As the edges lift off the plate, they become taller than expected, and the nozzle starts rubbing on the previous layers. This would be more prevalent on outer walls since those solid sides would also tend to warp (lift up) more than the thinner/less dense center. And the taller an object, the more that becomes an issue (especially if the part keeps warping/lifting more as the print progresses).
If I’m right and this is a new thing (same part(s) used to print fine), perhaps the plate needs a wash (or roughing up or replacement)?
Cheers,
-Max
Hi! Thanks a lot Max for your answer.
For sure, at least in this piece, it is warped:
But it is weird that I’ve tried this model like 2-3 times to print and always de left part is the “damaged”.
Plate was previously washed and then applied a bit of hairspray to extra stickiness. But yeah, still warped.
Actually, I tend with me pieces to use Brims and I haven’t used them in this model. Next try I’ll try with them. What else can I do to prevent warping?
That’s rather banana-like, indeed. 
A brim should make a significant difference. It’s not that unusual that it lifts from the same side every time, because… physics. I’d maybe check that there isn’t a cold draft (or similar) on part of the plate (like from an A/C vent perhaps).
Avoiding warps in general is quite an extensive topic in itself. There’s a very comprehensive post about it on these forums, which is probably a good place to start: Large Prints: Say Goodbye to Warping! There are certainly other resources out there about it, and of course the issue isn’t unique to BL printers.
-Max
Additionally, consider using some old bedslinger tech as a last resort of a skirt height = to top of the print. Back in the day, skirts were also known as draft shields, designed to retain heat for slower cooling. Naturally, these use a bit of filament.
Also, locate the parts away from buildplate corners. While the bed adhesion must be maintained, the strength of the shrink can lift the plate off the magnets.
Take a look at the default PLA softening temperature for reference. At this temp, the plastic is maleable. Consider the inside the print temp when removing the buildplate and/or print from the plate. Without the support of the plate while cooling, the print will continue to warp AND leave residue on the plate, causing future warping unless thoroughly cleaned. The best way to remove a part is to allow complete cooling. Parts should come off with very little effort. This extends the life of the plate especially avoiding the PEI coating from delaminating.
Thanks guys I feel very grateful with your responses, I’m learning a lot!!
I’m going to try this:
Rotating the piece to see if the same wall is getting damaged.
Plate just washed.
And I’m going to use Brim:
I’m going to see what it does and then comment results.
Oops, failed test! If you see the imgs, at certain layer heights it starts to rub the nozzle.
The other wall looks way better, and this time there is no warping, so warping is not the issue is causing this.
I feel super lost! I don’t know what could happen… something with the Z axis?
At every print I run the Auto Bed Leveling + Flow Dynamics Calibration…
Thanks a lot.
