The customer wanted a minimum width of 42" in Unfigured Western Maple on this project. The welded and gusseted steel base must be rigid enough to avoid flexing with the 225 lb top on it. A top of this size could move as much as 1/2" seasonally, so the base must be constructed to allow for the normal wood movement.
Starting a LE Slab project with rigid ideas of dimensions and color and patterning is usually an exercise in disappointment. The slabs are somewhat available, but each slab has its own character and shape. They are not a commodity. Trees are full of what we often call blemishes and flaws. When we bring lumber in the boards are mostly clear because they have been graded out for their clear qualities. Taking a long slice of a tree, the disagreeable features are often an integral part of the whole slab; because the entire slide from edge to edge is used, there is no opportunity to cutt around the unwanted portions. To get the good you will probably have to make friends with some of the bad. Its an adventure and I prefer to get to know the final table owner and their leanings and likes.