Source
From the campaign:
Introducing Hrothgar's Hoard's Wizard series of dice towers
I use the same concept of construction for the dice tower as I did for the Rogue and Priest line of miniature cases. I use a single piece of 8/4 lumber and, using a precision CNC, hollow out the interior so that the randomizing chamber is cut from one piece of wood. No part can come misaligned and no joints can come undone. One thick piece of wood is hollowed out, giving great randomizing results and a very sturdy construction model that will outlast the popular plywood models that are sold at conventions and gaming stores.