Solved: Metric viewport scale factors - Autodesk Community
forums.autodesk.com › t5 › autocad-forumMay 09, 2012 · Therefore, in the SCALELISTEDIT dialog box, a scale factor of 1:250 is 1 paper millimeters and 0.25 drawing meters. Remember, paperspace is a 1:1mm environment (i.e.. a 24x36 Arch D sheet would be drawn 914mm x610mm) so scaling a viewport for millimeters is a direct translation (i.e.. 1/10), whereas scaling a viewport for a site plan needs an "extra" translation of going from meters to millimeters.