Is there a default value for welding meshes? Seems like when I create a mesh via script the welding looks “funny” compared to creating a similar mesh via normal Rhino commands… But I can’t find an indication of a “default” weld setting anywhere so far.
I think this depends on which meshes you are dealing with.
You might see a difference because Rhino’s meshes are often not welded. For example, the sides of a box are not welded. In order to construct a non-welded mesh, you need to set as many vertices to the same location as there is a need for a normal. At the corner of a box, 3 normals and 3 vertices, for example.