all edges are perfectly vertical why is this happening?
Upload the file so people can look at it.
if you want to analyse Normal direction use the
you screenshot shows the gumball - the blue (z-) direction depends on
_gumballAlignment- that can be Cplane/Object/World or freely adjusted…
the artefacts of your surface look like a meshing - problem.
save the File with a new name and choose option “save small” close rhino maybe restart and reopen the “save small” file. - this will force rhino to recalculate the render-mesh.
to make sure / analyse if it is the render-mesh, you can
_extractRenderMesh and look at this mesh.
delete face and _cap
… might be other approaches
and yes as @christopher.ho told you: post the file with only the affected polysurface and we can help better.
good look - best -tom