Holes in model. Nnon-manifold

I am making some great models in Nomad but I am getting holes in some models and my slicer software says the file is non-manifold.
This is not about slicers

Is there something I need to be aware of when making a model using a mask?
I created a cylinder and drew a mask onto the shape. I extracted the shape into model and then applied a stamp texture on the model for texture and then exported it as an obj. I tyried stl also just to see if my results improved.

That obj has holes.

Maybe a bug in Nomad.

Do you see the issue visually?

Not in nomad.
I’m going to export it again to see if it happens in the same location.

I did see holes when I imported the file into either Simplify3D or Lychee Slicer but now that I am trying again I don’t see the holes but the slicer says I have 236 holes detected and the model is not manifold.
I get 236 holes in the exported STL and 236 holes in the exported OBJ.

I used the model-checking tools of Simplify3D to look for non-manifold edges and it found a few.
I also used the 'Identify self-intersecting surfaces.
Both screen captures are attached.

Hover over picture, each is named.

Non manifold edges can appear but not hole per see.
Typically produced by hole filling algorithm or dynamic topology.

Self intersecting surface is not surprising either, smoothing can helps.

Voxel remesher ensures the topology is clean.

By visually I meant to display the wireframe and zoom on a problematic area to see exactly what’s going on (when there is a topological hole, using the smooth tool will make the stretch but normally Nomad doesn’t produce any hole).

If the file is small you can send it to me.

This is from Recap Photo’s analyzer;

The pics below are from Meshmixer and start zoomed in and then different pics while zooming out.:

It looks like the non-manifold(?) issues are in large part created from thickness created from Extract or Split inside the Mask tool. i think it was the split…I
I’m not positive though.

I can send the file to you if you still want. It is currently 96 megs so I will need to slice most of it out before sending it to you.
If you do want it how to I get it to you?

stephaneginier@gmail.com, you can zip the file.

I cut part of the file away , zipped it and emailed it to you.
Thanks .


As I thought there are no holes but lot of weird non manifold thing.
I suppose it’s coming from the hole filling algorithm (assuming you never used dynamic topology).
I don’t have any fixed for that though.

Understanding how it happened in the first place could help me pinpoint the issue. I can’t reproduce it.

Until then, using the voxel remesher always ensure a manifold mesh…

I had not used dynamic topology.
I cant use voxel remesher because the imported obj files (not made in nomad and not quad mesh) loose their detail.

I could not find the file that showed me the holes and i cant recall how It came about as the model is approaching 2 gigs so I have to work on the pieces separately and then once together I can export as an obj.