To clarify my previous message, I build the each surface (patch) going from points->lines->line loops->Plane Surface or Ruled Surface. I am not merging STL or IGES files. Cheers and thanks, Mike. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.geuz.org/pipermail/gmsh/attachments/20090805/bd695ea2/attachment.html>