Can't close Surfaces into a solid, can anyone help?

Hello, everyone!

I am designing a staircase using surfaces, when I try to join all the surfaces to form a solid something goes wrong and one point shows as a naked edge.
I tried everything I know, creating new surfaces from adjacent edges, patching, matching surfaces…, but this point always remains opened.

I must have a solid object to import in Revit or Autocad3D for the guys manufacturing the concrete forms, they asked for surfaces, not meshes.

Can anyone help me? Thanks in advance!
B170_S04_R00_v05_ramp-only_part2.3dm (2.4 MB)

Hello - this has one of those pesky ‘point’ edges that won’t close. Use the command

RemoveAllNakedMicroEdges on this.


Thank you very much, Pascal!! that did the trick, didn’t know about this command.