Originally Posted by
dunster
You only lose 1/2 inch when going from the 9p to the d9p, because you're just slicing and then making one 1/4" seam, which removes 1/4" from each piece.
Yes, which means for a block to end up 12.5 it would have to be 13 inches before you cut it. 13 does not divide evenly by 3.