Scant - yes...almost. Just a couple of threads less than 1/4 to account for the pressed edge. You'll end up having a sliver to cut off for perfect size. Try it like you always do and also with scant....see what works best. I pieced the entire SBS (pieced blocks) using scant and had very few blocks come up short. Made assembly so much better to have everything the same size, obviously. Anywhoo....the first block of GTSB is also in the SBS and is also unfinished 6 1/2. SBS = A1 / Mosaic No3.....in GTSB book it's called Wedding Chain Block. Each square is a diff fabric. So, see? You can make a block before the book gets there. You only need one of this block....*wink* (I shared a pic above of my block)