If you haven't looked there, try searching on "large volume" at 3dprintboard's parent, 3dprint.com. That at least brings up a number of articles on large format printers that might be of some help.

I might have been clearer on the home/hobbyist angle. IMO, those are the areas where you'll find people sharing ideas. IMO, those that know how to create a printer like you're hoping to build aren't likely to be giving away much detail. They're going to be wanting you to buy their machine...