Cura and strange behavior with overhang

[Ju3D 0]

                Hello

 

I am rather newbie in the 3d printer world, but I can learn quickly.

I was a bit astonished by Cura behavior when trying to print brutal 90° overhang piece, so I printed a very simple model, an inversed " L " shape . I tried without support, with tree support and with plain and efficient support, same result.

What I visualise under Cura (3.4.1) in layer mode, is exactly what I print, no problem , but it isn't the simple L shape that I have under blender.

Cura added some kind of inversed pyramidal shape under the 90° overhang. It may be normal, to make the object printable, it may be configurable (where?) , but I didn't see the answer anywhere.

Does anyone know ?

Below, the Cura capture where we can see the little yellow protuberance which is my inversed pyramide. And the printed part, with its support, upside down. The pyramide is plain to see.

 

              Thank you

[gr5 2,230]

The feature you want to turn off is called "make overhang printable".  In your screen shot just above all the settings do you see that box that says "search..."?  Type "printa" there.  It will then show even invisible settings.

[Ju3D 0]

Thank you very much for your answer. If i disable this and launch a print with a full support, like in the picture, is it supposed to work or the support function is only to support the global structure, the poise,  and not  each micrometer of melted abs  , here, my 90° overhang ?

 

[Ju3D 0]

The late conclusion for this topic. I could print the inversed " L " without the pyramide pattern. I followed GR5 advice (thank you again) and unchecked "make overhang printable" and it resolved the problem.

My second question was about printing in thin air over support. I will learn with time, for the moment it isn't fully satisfactory, in my resulting print there is a slight slope which is about 0.4mm over 15mm distance. Not much, but I wonder why. It doesn't appear in Cura slicer. In Cura, the distance between support surface and printed model is 150um which is quite inferior to my mysterious 0.4mm.