Why does Cura close the top hole in this print?

[anderespeler 0]

Cura closes up the top hole on my testpart for a screw-on component. What could be the reason this happens?

Cura doesn't seem to give any warnings about issues with the model.

 

I included the project, the stl file and the g-code.

Around layer 77 the slicer goes inwards and closes up the hole.

 

This only happens when I slice the part vertically, not when I slice horizontally.

I use the standard Standard Quality settings, with tree supports from builtplate and wall line count = 6.

But flipping those back to default values showed these don't seem to be the issue.

 

I already tried a few tricks mentioned in similar topics:

- disable Union Overlapping Volumes does not fix it

- "model isn't watertight error" does not show up

- changing top/bottom thickness to a ,01 decimal does not fix it

 

Thanks in advance.

CE3PRO_Opwind_TEST2 Draaiknop v20220412.3mf CE3PRO_Opwind_TEST2 Draaiknop v20220412.gcode Opwind_TEST2 Draaiknop v20220412.stl

[GregValiant 1,330]

Cura points out problems with the model graphically and with the popup.  I tried to repair it with MS 3D Builder but no luck.  You really need to re-do the threads in CAD.

 

An on-line repair service gave this report but was unable to repair the model.

From https://formware.co/OnlineStlRepair

-> Analyzed your file:
--> 25 Naked edges (?)
--> 0 Planar holes (?)
--> 0 Non-planar holes (?)
--> 119 Non-manifold edges (?)
--> 180 Inverted faces (?)
--> 0 Degenerate faces (?)
--> 38 Duplicate faces (?)
--> 0 Disjoint shells (?)

 

 

 

 

 

[anderespeler 0]

I tried the tool suggested in this topic and it completely removed the threaded hole from my stl part. So perhaps there is an issue with my part.

 

OnlineStlRepair

 

[GregValiant 1,330]

This is zoomed into the top portion of your threads.  All of those facets indicate errors in the model.  The blue areas indicate open edges that confuse Cura because the program can't tell the inside from the outside.

 

These threads happen to be male but you can see that there isn't any of that "faceting" that is apparent in your model.

[anderespeler 0]

Thanks Greg.

The error message didn't show up in my Cura.

 

I wonder why cura was able to print the threads in a horizontal orientation, though...

[GregValiant 1,330]

When a model slices differently in one orientation as opposed to another, that is one of my indicators that there are problems with the model.

Cura slices horizontally and so with the model rotated onto it's side it looks totally different to the slicing software.