I am looking to combine two objects into the one shell, since the Boolean operations in Maya are not always trustworthy, often I end up with no model at all, I am wondering if there is a good way to...

Thanks for all of your input. In the end I found this worked the best.

Select All faces of model, and choose Edit Mesh > Extrude Options, and apply following;

1 Division
0 smooth angle
0...

I have tried internal extrusion, but because of the shape (it is not actually a box!) this does not have the desired effect. Because it is a complex shape some of the internals need to gt bigger,...

I have a box model, I am looking to print it with a 3d printer. However the printer wants to fill the model's volume, and I only want thin walls around the edges, so that the model is hollow. Is...