I woukdn’t do a string with pieces that small. By the time you sew seam allowances, the width is only 1/2 inch. And 5 inches would only cover the diagonal if a tiny block.
Maybe try one coin collection block instead and see if uou like it. I do doll quilts in that pattern—but not with anything narrower than 1.5 . Just don’t have the patience to work with teeny pieces.