Cannot figure out why this won't print / is non manifold

[dario33 0]

Hi guys,

 

I cannot for the life of me figure this out, and I'm ripping my hair out. If you could please help me out here that would be greatly appreciated.

I have this model of a cylinder, that has holes in it and cone-like structures in the middle, everything is fine when I want to print it out like this: 

But, when I add another cylinder on the outside to serve as a sort of shell, and connect them up, this happens:

 

and then none of the inside actually prints out. 

 

Could anyone please explain to me why this is happening? I'm attaching the STL.

 

Thank you in advance for any help. 

 

cylinder.stl

[ahoeben 1,955]

Here is an explanation about what "non manifold" means:

https://github.com/Ghostkeeper/SettingsGuide/blob/master/resources/articles/troubleshooting/missing_parts.md#non-manifold-meshes

 

A cross-section can never have an uneven number of walls; Cura needs to be able to figure out what is enclosed between two skins, and a single skin must allways be inside on one side and outside on the other side.

 

I think you mean for your outer cylinder to have thickness.

 

Edited May 20, 2022 by ahoeben

[dario33 0]

1 hour ago, ahoeben said:

Here is an explanation about what "non manifold" means:

https://github.com/Ghostkeeper/SettingsGuide/blob/master/resources/articles/troubleshooting/missing_parts.md#non-manifold-meshes

 

A cross-section can never have an uneven number of walls; Cura needs to be able to figure out what is enclosed between two skins, and a single skin must allways be inside on one side and outside on the other side.

 

I think you mean for your outer cylinder to have thickness.

 

Honestly, I have tried all sorts of thicknesses, different vertex merges, I've been sat at this all day and I can't figure it out. The closest I can get is this:

But I need filament to be where I have scribbled in red, and I just cannot figure it out 😞 

[ahoeben 1,955]

The inner cylinder has holes in it. Where do you want those holes to end? This question is an important part of what is confusing Cura.