Originally Posted by Bluphrog

By knife edge, do you mean what I call a floating border?

I cut strips 1" wide, fold and press wrong sides together, then sandwich between the first and second borders. When you sew the border on, it makes a neat 1/4" border (kind of like a flat piping, if that makes any sense). In this case, it would lay on top of the white border, and would really set the purple floral off.