This is a fully defined 3D sketch. Two 3D arcs are in outside. When I exit from the sketch mode, I could see two 3D arcs have gone inside. What is the reason for that?
I don't know why it's doing what it is doing. I would think that this is not intended behavior. Although I was sometimes successful by deleting the arcs and adding them back in, It was not consistently behaving like you would expect. What I ended up doing was to make some construction geometry (sort of like a style spline) on your 3d plane1 and adding tangent relations to the arcs in order to force it to consistently end up like I wanted.
In addition I draw a line like this it works.
Retrieving data ...