Rhino 7 - mesh - ngons not weldable?

good evening,

is it possible that there is an issue with welding ngons with 4 sided mesh faces or is it my fault?

ngoonz.3dm (182.0 KB)


obviously i am not able to weld these 4 mesh faces too. usually adapting the angle tolerance works like a charme.

what I am doing wrong?
meshes.3dm (169.7 KB)

Hi Benjamin.

Your mesh has tow pairs of coincident vertices which can be stitched using _Stitch

Is this what you expect to see or did I miss something?

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hey Martin,

thanks for your fast reply! the result of the naked edge analysis is as expected. there where 4 faces and two of them welded.

uh, i didnt know the stitch command, just tried “weld mesh” and “weld mesh vertices”, shouldnt they work in this case?

stitchmesh does not work either, or I am just to tired today?

nice climbing walls btw! :slight_smile:



A Stitchmesh command does not exist in Rhino as far as I can see.

Your mesh does not contain any unwelded edges.

Weld | Rhino 3-D modeling (mcneel.com)

According to the help file, _WeldVertices should weld the vertices and I don’t know why that’s not the case on your mesh.

hey Martin,

there is a stitch command for meshes in rhino, but i cant select two edges for the stitch, because they are too close together.

somehow the standard commands dont work either, i have no clue, propably it has to do with tolerances, whatever.
this is just a small example out of a larger mesh and I dont want to remodel it. WIP 8 is not welding the vertices either.

thank you,

If you’re referring to the command in the Mesh tab, then that is the same stitch command I was using.

I just tried again.

I ran _MeshRepair first and then _WeldVertices and that seemed to work.

The mesh now has 10 vertices.

You get this info with the _What command

good morning Martin,

thank you for your effords, i tried to check the mesh like you and had interesting results:

after repairing it:

nakes edge analysis:

welding vertices:

mesh normals:

i somehow dont get it.

this is the combination with a ngon after unifying mesh normals (a good mesh btw):

have a nice day,

uglymesh.3dm (197.9 KB)

Not sure where things go wrong on your side. I think Rhino 8 has a lot of improvements when it comes to meshes. But I see the normals are bad on this latest file too.

Try _RebuildMeshNormals

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ok, that looks much better. propably the mcneel guys know whtas happening here.

thanks you for your support!