So I got a bunch of wood that is 3" wide and 12 inches long. poplar, cherry, maple, hickory, walnut all solid wood some 1/4" some 3/8". Most of what I have done is on plywood so size is less an issue and magic fingers are reasonably strong in any direction. Not so much in solid wood.
I made one first at 3"x4" and discovered that magic fingers have an issue.
So I tried a different design that was 3x3 and was able to get 4 on one piece of wood and the top and bottom on half of another but it was very tight. but there was not much room for scrap.