Mesh breaking apart?

[dk79]

Hey there!
I’m having an issue at the moment with a mesh I built right inside Zbrush.
I extracted the object from the mesh of the body to create a shirt. After working with it for a while I discovered that the mesh isn’t connected as you can see in the picture below.
When I go back to a previously saved version if I watch closely I can see that the problem was there when I first extracted but it was barely visible
Since the body mesh I extracted the form from, is solid, I don’t understand why this is happening.
Any ideas would be greatly appreciated!!

[aurick]

I’ve never heard of a case where an extracted mesh had unwelded points when the source mesh did not. Are you absolutely sure that the points are welded in the original?

As for how to fix this, you can export the extracted mesh. Select the Polymesh3D tool (the star) and in the Tool>Import menu crank up the Weld slider. Then import the extracted mesh again. This will weld the points, and you can append the model back onto the source.

Alternatively, you could use retopology to delete the offending points and then stitch the model back together again.

[dk79]

Hey aurick. Thanks for taking the time to reply.
As it turns out there were 4 polygons that had reversed normals on each side.
So what I did was export an obj at lower subdivision reverse the problematic normals and then reimport back to zbrush.
I pressed the reconstruct higher subdivision and I had to smooth the problematic parts but other than that, it seemed to work.
Now when I extract the shirt I have no problematic parts.
Did I do it correctly or do I need to do something else?
I’m saying that because the first time I did the exact same thing I had the normals reversed again, so I don’t know if I got it right by sheer luck or if I’m gonna get the same problem again at some point later on.