It all works fine until someone drags a sleeve across the table and the tiles move around. He needed some way to keep them from moving and this Instructable shows what we made.
Brother Bob would do a layout, I'd create tool paths, then I'd cut it on the ShopBot at TechShop, Menlo Park. I did a number of prototypes with different cut depths to find the perfect fit. In the end, 0.05 inches seemed best - the hex cards fit well and could be lifted up easily. Note how there is just enough space between the tiles for the "road" pieces to fit.
The board is in three pieces. Two pieces fit together to make the standard game layout. If you play with the expansion pack, then third piece is put in the middle. We tried several different layouts for the edges until we settled [pun intended] on the layout you see here. We went through 10 different revisions to get this final design, not to mention the numerous tool path tests of each revision.
The photo with the tiles on the board shows how well it all fits together and how nicely the tiles are held. Now when a player gets excited over a good roll of the dice we don't have to spend ten minutes putting the game back together!
my web site
Brother Bob's Web Site with many more photos and ideas