Imported mesh from blender has a hole

[3trois]

Hi, I'm following this guide and I have this mesh I've made and imported. It has a hole in the top mesh no matter how I turn it.

In blender it has the same design as the bottom.

[davescm · Accepted solution]

It looks like reversed normals.

Go back to Blender. In edit mode, select all, then recalculate the normals to be outside. 

Following that, you may need to re-unwrap before exporting again.

Dave

[3trois]

Yes! That did it. Thank you.

Can you explain what was wrong?

[davescm]

By default, in viewport 'solid view' Blender doesn't distinguish between correct and incorrect normals. It shows both front and back faces as solid.

Substance only shows solid on the front face as determined by the normals.

So the root cause was that the normals were incorrect on parts of your model. You can check in Blender's edit mode by turning on the face normal indicators. Always a good check to carry out before unwrapping.

Dave

[3trois]

Great! Thanks. Learned alot.