The cockpit of the Millennium Falcon model was made by building a rough "core"
(out of two round pieces of styrene in two different diameters, to get
the cone shape) and a couple extra pieces between these two disks to keep
the proper distance between them. I then wrapped three overlapping layers
of thin styrene around the core and glued them together. (NOT onto the
core though. The core is just there to get the basic shape and will be
removed later) I then first scribed the windows into the cone and then
cut them out. I used a piece of 3" tubing to build the cockpit tunnel onto
the upper dish.