Maya smooth mesh problem

PolyHertz

I'm having a problem in maya 2k9 where when using the smooth mesh preview (3) random edges are becoming pinched. They have nothing to do with hard/soft edges or creases, and after many hours of trying to find the cause the only thing that seems to remove them is exporting to obj and re-importing. Obviously exporting/importing every time I want to see a mesh with proper smoothing isn't a very useful solution, so I was wondering if anyone knows or has any ideas what might be causing this?

example images:

MoP

Have you done a Bridge on those polys?
It's a bit buggy if you use Bridge on a single or double quad strip, it doesn't weld the edges sometimes, so you get 2 verts which have TWO EDGES running from them (I have no idea how this is possible, and it's really dumb), usually I use Fill Hole instead to join up enclosed polygon strips.
My guess is the only way you'll really fix this is by deleting those 2 quads enclosed by the "broken" edges, and re-build them using Fill Hole.

PolyHertz

Huh, yea I'd never considered that sense as far as I know it should be completly impossible. But I suppose that could be mayas slogan: "Making the impossible possible, whether you like it or not".

Thanks mop

ivars

Easiest way to fix it is by just selecting all the verts around the trouble area, choose detach component and then merge with a very low distance threshold.
If you turn on Border Edges under polygon display you should be able to spot the problem areas.

malcolm

Looks like you done a crease verts or crease edges, try deleting all your creases?

ivars

could also be a case of lamina faces. Run cleanup on your mesh to get rid of any nastiness.