Conception flaw or a bad hotend replacement ?


This came from my Bambu P1S, I did a hotend replacement a week ago and I only print simples models since.
This time I tried to print a model a bit more complexe with supports and it failed.
Filament is dry, ambiant humidity is 7% in the AMS.

Do you have any suggestions ? Thanks

Tato položka byla upravena (4 months ago)
in reply to Schmaker

You are right !
I did a second try, with a different preset "0.08 High Quality". It also failed.

The timelaps show the hotend hitting the model base. ( see this streamable )
It's the first time it happens, I don't know what to do to fix it 🤔

in reply to gdaofb27584

Looking at your video, that's definitely a nozzle collision issue. Try enabling "Z hop when retracted" in your slicer settings (should be under travel options). This will make the nozzle lift slightly when moving between parts, preventing it from hitting your model. Also, for models with such a small footprint, consider adding a brim for better bed adhesion - looks like the impact is knocking it loose from the bed.
in reply to gdaofb27584

Check your bed adhesion (clean the bed with detergent and hot water, and I recommend a quick wipe with 91% IPA before each print) to prevent the model rotation seen in this picture, but in general parts with that little bed contact can be difficult to print correctly. If you can’t find an orientation that fits on the bed with more surface area, then slow the print down to minimize forces pushing the print. While supports help, they don’t hold onto the print as firmly as the bed does (on purpose).

I’ve run into some frustrating issues with small contact points with print beds. Another option is to use a smooth PEI plate and use a glue stick or Bed Weld or something to help improve adhesion.