I found an EXCELENT diagram of the forces... in a [:-]1938[:-] Model Airplane News magazine.

Now to get it scanned.... The article its in is dealing with how to build a model that MUST self-level, as its a free flight model. But the description and diagram of the forces involved is very complete.

Can't really ignore gravity in knife edge... its a force acting on the model... and compensating for it causes other forces to come into play (using rudder and trying to fly on the fuselage side area... and correcting for roll with ailerons... and....)