Much thanks to [log in to unmask] for the best explanation of "sign board" that I have experienced. For my next purchase I am going to ask for high-density overlay and see what happens. It is a possiblity that I have been getting that, as what I have been using has not been painted and just will not warp. Make no mistake, this stuff is expensive. However, there is no waste due to wood defects and no lost labor due to stuff that has to be destroyed because of warping. I compared the cost of making 5-frame nuc boxes out of this and buying similar boxes and it was about the same...but I got a box to my specs. instead of having to accept someone elses bad ideas. On the other hand, around here one can buy first quality deeps of high-quality northern white pine for just $7 each, so I use those and just use the sign board for tops. Lloyd -- Lloyd Spear Owner Ross Rounds, Inc. Manufacture of equipment for round comb honey sections, Sundance Pollen Traps, and producer of Sundance custom labels. Contact your dealer or www.RossRounds.com <http://www.rossrounds.com/> -- Visit www.honeybeeworld.com/bee-l for rules, FAQ and other info ---