There is no "legal" definition of a scant quarter. I've heard it described as a "few threads" short of a quarter inch. HUH? So I use my quarter inch foot, which has flange that you run the cut edge of the fabric against, and just make sure I don't push the fabric up tight against the flange. I make sure I can see some space between the cut edge of the fabric and the flange. Here's my bottom line - as long as I'm consistent then things work out. I often say "if you're going to be wrong, be consistently wrong!" I doubt the bargello has any blocks that you can measure to ensure you are at the right measurement. That works for traditional blocks - make a sample and then measure to ensure you have the right size - but maybe not in bargello. Just be consistent!