Ways to eliminate non manifold edges?

I’m trying to make an object for 3D Printing. I’m using subdivision surfaces for the final form.

I’m puzzled. I used the Non Manifold Edge button in the Print3D Toolbox. It highlighted some surprising edges on the control object.

I removed some obvious things like an extra vertex and hidden face. But when I removed them other edges went from manifold to non-manifold. The edges are not connected, so there was no change in them.

I’ve checked all the typical problems, missing or extra faces, edges and vertices. Checked that no edges have 3 faces. I selected points with the border select and scaled all to zero and them removed doubles(no verts were removed). I’ve deleted the faces and rebuilt them. But the non-manifold edges persist.

Any ideas of other things I can test?

Check in Face selection mode to see if those edges are not marked as faces, or if by any chances you have internal faces at the base of your finger.
Or upload your blend so someone can check if there’s something else that is not obvious on that screenshot

well, as you appear to have a massive Ngon for the paw i would figure that that is causing the edges to read as non manifold. as for the claw, nothing is obvious there.

Thanks for the suggestions. I found no internal faces or other debris. I tried replacing the ngon with a quad and two triangles, and that didn’t fix things.

The oddest part was that these edges were considered manifold until I removed some garbage a couple of polygons away.

From looking at the images your problem is eighter hidden, overlapping, not connected geometry and/or inconsistent normals.

First thing you should do is make sure you have no hidden geometry (alt+h), then select everything (a) and remove doubles (found in the specials ‘w’ menu), and recalculate your normals (ctrl+n).

If it’s still not gone, post screenshots in vertex and face mode, as you can see other stuff there too.

if possible try to upload the file
might be faster to analyse it !

happy cycles

gexwing, I had tried that already. No luck. What I ended up doing was to make a copy of the rear foot, and delete the front foot and leg completely. I then positioned the new foot, and rebuilt the front leg. That seemed to do the trick. The big thing I learned to watch for was to click the Solid button in the Print3d toolbox before reclicking the Non Manifold Edge button to make sure I have the latest changes to the model.

And after doing that, I got stubborn and went back to the original got nasty and found some what seemed to be edges without end vertices, so there were double edges without faces. Fixing that seemed to work as well.

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