Modifier Error: Non-manifold mesh as input

i imported a large .3ds model and now i need to decimate portions of it cuz its a

81MB BLEND!!!

but when i apply the decimator modifier i get the following error
“Modifier Error: Non-manifold mesh as input”

whats up with that?? how else can i reduce the filesize if i cant decimate?

Means there is superflous geometry somewhere. Remove Doules then goto Select >> Non Manifold with no verts selected. Any verts selected after that will show where the problems are.

You can also try the Clean Mesh and Cleanup Meshes scripts.

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i knew u would have the answer fligh %, don’t ask me how, i just knew.

ok, my mesh is DOOMED to be non-manifold for the duration of its natural life. every time i select and delete the non manifold verts and/or edges (i tried both) - i still have some more - i keep doing this until 98% of my mesh is gone and then its manifold.

trouble is that the mesh is ductwork (took me one day to model accurately)

is there anyway to decimate it or lower the face/poly count on a non manifold mesh?

You could try Cambo’s ‘PyRedux’ script.

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