You can use VDrop and V Orient by Max Smirnov
for see normals of "One" surface and orient them
http://moi3d.com/forum/index.php?webtag=MOI&msg=11019.1

https://moi3d.com/download/scripts/max/vDrop.v.1.0.2014.01.28.zip

https://moi3d.com/download/scripts/max/vOrient.v.1.0.2014.01.28.zip