Thanks for your answer Tomas:
Split command needs a tool ;such as workplane,face,.. which doesn't exist.
It is reallay what I want to create to decide the faces of my mold.
In MDT6; I use the part line Command and I get a speline or polyline all
around the part,then I create surfaces to split the part.
The part lines are almost allways 3D spline in the models which I recive
from our customers.
How should I do this in Inventor now,If we decide to forget about the
MDT????
Sepehr