Thanks for the board design. I scaled down your latest design with the tail mod to 28" then sliced it in NetFabb. As others found out the inner structure did not print with a .4mm nozzle, I changed the my nozzle setting to .3mm and adjusted the feed rate and it printed. Assembling it was not easy, the center structure printed as a single width which made it very fragile.
The printed board was glued together with Medium CA, coated with PVA and then ironed on a thin Mylar.
3DimensionalTools.com Komodo XL