Ultimaker Cura 5.8.0 slicing issue at Voron profile

[VUHA 0]

Hi Experts,

 

I have slicing problem under Voron2 printer profiles. I have attached some pictures about phenomenon, which is reproducable. It looks like as wrong slicing algorithm (random zigzag nozzle paths). The 3D model is a one of original Voron part.

 

Could you tell me, what is this phenomenon? Is this Cura issue in case of Voron interface? How could I avoid, or  workaround this problem?

 

Model link: SIBOOR-Voron-2.4-AUG/STLs/Decorative print stl/Panel_Mounting/corner_panel_clip_6mm_x8.stl at main · Lzhikai/SIBOOR-Voron-2.4-AUG · GitHub

3D Printer: Voron2.4 R2

 

PS: This issue goes away if I choiced any else Printer (Ultimaker 2+, Sx, Anet, Custom FFF Printer etc....)

PS: The problem is tha same at previous Cura release (5.7.2)

corner_panel_clip_6mm_x8.stl

[Slashee_the_Cow 619]

Hi there!

 

If you could post a Cura project file (.3mf, get it set up then go to File > Save Project) that would be much more helpful because it includes your machine and quality settings, especially if it only happens on a particular printer.

 

It certainly can't help that (I think this is the fourth time I've said this today 😑 your model is bad. There are almost no faces on the inside (the polka dots are how Cura shows that):

You should have gotten a warning when you loaded the model in Cura that it had missing or extraneous faces. It also looks like some of the faces on the outside (at the start of the chamfer on the base, and especially on the corners) have their normals flipped:

There are free online STL repair tools (just search "STL repair") or if you're running Windows, Microsoft's "3D Builder" app is very good at fixing broken models.

 

With that out of the way, as for why all this gobbledy-gook is only appearing on a certain printer? That's what we need the Cura project to try and find out, especially since it doesn't seem to be in the model.

 

Although for all the bad models I've seen today yours definitely comes closest to slicing properly 🙂

[VUHA 0]

Hi,

I used the defaults. There was no warning. The used external stl model was verified in Blender. I have attached the requested .3mf file. I am newbie here and 3D printing world, so any comment could help me to understand the basics.

PS: I used this at this moment, but the issue is the same like before. Link: Free online stl repair tool (formware.co)

V350_corner_panel_clip_6mm_x8.3mf

[Slashee_the_Cow 619]

It's not just an issue on the Voron. I get the same problem on my (custom) Ender-3 V3 SE profile:

And to a lesser degree on the stock E3V3SE profile:

 

I'll be honest. I have no friggin clue where it's getting those weird shaped holes from.

The actual solution part: Set Top/Bottom > Skin Expand Distance to 1mm.

[ahoeben 2,047]

On 8/3/2024 at 12:03 PM, Slashee_the_Cow said:

There are almost no faces on the inside (the polka dots are how Cura shows that):

It looks like you put the camera *inside* the model. Cura will always show the polka-dot pattern if you do so (actually, it would indicate a problem if it didn't).

 

The polka-dot pattern is shown if a ray going from the camera through the model at the point of that pixel goes through an uneven number of faces. For a solid, manifold, concave model, any ray from the camera through the model passes through exactly 2 faces. After the first faces the ray passes, the ray is inside the model, and after the second the ray is outside the model again. Say that same model is hollow, but still has a nice thick wall. Then depending on the position of the camera, there are parts where the ray still passes 2 faces (only goes through the wall, never hits the internal hollow), or it goes through 4 faces (outer wall, inner wall, inner wall, outer wall). If the ray ever goes through an uneven number of faces, then the model either has a missing face or it has an "extra" face. Cura highlights those areas as broken/needing repair.

 

Now if the camera is *inside* the model, a ray from the camera is always going to pass one fewer faces (since the ray does not have to enter the model). So everything is marked as "broken".

 

In short: don't put your camera inside the model and expect the display to make sense.

Edited August 7, 2024 by ahoeben