Holes in certain thin walls

[qwirty123]

Is there an existing issue for this problem?

• [x] I have searched the existing issues

OrcaSlicer Version

2.0.0

Operating System (OS)

Windows

OS Version

Window 10

Additional system information

No response

Printer

Bambu Lab X1 Carbon

How to reproduce

I stumbled across this in this model of a spiral, the there are holes in the thin walls. This happens whether with step files or stls. Interestingly, it only happens with the model on plate 1 and not on a nearly identical model on plate 2. I used default presets. See the attached file.

Actual results

There is an oddly shaped hole in one of the thin walls.

Expected results

There should be no hole.

Project file & Debug log uploads

bug_report.zip

Checklist of files to include

• [ ] Log file
• [X] Project file

Anything else?

No response

[discip]

@qwirty123 This is not caused by the slicer as your stp/stl is corrupted:

Please close this issue since this is not related to OrcaSlicer. 😊

[qwirty123]

@discip Interesting... Could you see the attached step file and see if it is corrupted? My concern is that there is an issue with the conversion from step to mesh. It is straight from fusion360. Yet when I export as mesh from f360, it is perfectly fine. d2_11.zip

[discip]

Unfortunately this is corrupted as well. 😟

[qwirty123]

There seems to be a bug in the conversion from step to mesh. When you use another tool to convert from step to stl, there is no corrupted mesh.

[discip]

You don't need to convert to stl. Orca can use step / stp files as well.

[qwirty123]

That's what I'm saying. If you use the step file, there are holes; but if you convert the step file to stl first and use that, there are no holes. Thus, there must be something wrong with the way orca handles step files that causes holes.

[foreachthing]

I've seen "corrupt" STEP files from Fusion360 here as well. When importing the STEP file into SolidWorks and export them again, everything was fine. So, yeah, Orcas STEP import has some room for improvement (specifically for STEP files from Fusion360).

[discip]

That's what I'm saying.

Ah, I see! Sorry, I thought you meant you used another method to convert to stl. 🤦‍♂️

[discip]

Please close this issue since this is not related to OrcaSlicer. 😊

My previous comment was made prematurely, as far as I understand after further investigation, and thus is simply wrong. 😓

I imported the original step file (https://github.com/SoftFever/OrcaSlicer/issues/5641#issuecomment-2158500819) into F r e e C A D, c a t i a and o n s h a p e. The result in the later two was flawless, whereas the first one showed the same artifacts as OrcaSlicer does.

So this indeed seems to be an issue with OrcaSlicer! 😯

[qwirty123]

It appears that this goes deeper than Orcaslicer as the same artifacts appear in Prusaslicer and Freecad. It's possible that it's a bug with the CAD kernel itself. On the Prusaslicer release notes for STEP support, it says

We use Open CASCADE Technology (OCCT) development platform to read the STEP files. It is a CAD kernel also used e.g. by FreeCAD or KiCad. Thanks https://github.com/Open-Cascade-SAS for keeping it open-source. The import implementation itself was ported from BambuStudio, thanks https://github.com/bambulab.

I don't have kicad installed, but I suspect it would display the same issues.

[discip]

@SoftFever @Noisyfox @igiannakas Have you experienced similar behavior? Is the observation that the kernel is not performing as expected correct?

[discip]

@SoftFever @Noisyfox Anyone? 😊