Parts of a model are black

[jakacbatko]

Hey guys!

I’m quite new to 3D and still learning. I searched forums and the web regarding this, but nothing works for me. Just one part of my 3D model is black after I upload it to Sketchfab.
I’m using Blender where textures are ok. I’ve uploaded the model with the Sketchfab plugin. I tried to replace textures. I don’t have the option for Vertex colors (as some posts suggest). I tried to upload the model manually with different types (zip, obj, fbx,…) and I tried different browsers and devices if the rendering would be bad or something.
I did get error when exporting .fbx but I’m not sure what’s the problem.

I’m guessing it’s something in Blender but I just don’t know what to do anymore.
If someone knows what’s wrong with my model, I would really appreciate the help.

Thank you in advance.

Here is model if it helps:

[norgeotloic]

Hey @jakacbatko

It’s indeed coming from a data issue on the Blender model, which gets cleaned during the Sketchfab processing, removing the UV mapping of this part.

To be more precise, some faces of your model are “degenerate” (they have an area of zero), as some vertices are duplicating each other. In order to avoid issues on Sketchfab, we clean them and remove some data which could be impacted by this in the viewer, along which the UV maps.

To fix this in Blender, you can select the parts of the model which have the issue, enter Edit mode (“Tab” shortcut), select every faces/vertices/edges (“A”), and use the “Merge by distance” option to merge those vertices together.

If everything goes well, this should fix the issue for you, as it did for me (the model below was uploaded through the Blender addon)

[jakacbatko]

Wow. I didn’t even know that option exists.
It worked!

Thank you so much!
And thank you for the quick replay.