I have a kitchen stool design with a deeply sculpted seat. The seat blank starts 2-2½” thick. The seat is structural; the legs mortise directly to it. I have some bigleaf maple burl slabs large enough to make seats, but wonder about the structural strength of burl. I can almost convince myself that burl is strong because it has grain fibers running all directions so there’s no split axis. On the other hand, I can almost convince myself that burl is weak because there’s no coherent grain pattern – kinda like particle board. I’m a little leery of the experimental approach, because it’d be a shame to waste burl on seats which are doomed to fail.
So, does anybody have experience with burl used structurally? Is it as strong as normal lumber?