I am trying to create a simple isometric square box that is rather large (the illustration is for a wall and the rectangle box before 3D extrusion would be about 80"x50"). However, when I try to make it this size it doesn't work and ends up looking like the attached. Anyone know why or how to fix? Why is it missing its center and why is it shaped like that, when the original shape is a simple rectangle? It works fine if the shape is much smaller.
Illustrator's 3D effect seems to have a z-axis boundary or picture plane of some sort and anything that extends beyond it (i.e. too far towards the viewer) is not rendered. You can see it on much smaller objects if you use a large perspective value.
I don't know if there's a way around it. The new 3D panel doesn't seem to have this, but also might not work for your needs for other reasons.