Have you tested your machine to see if where your needle is to make a 1/4" seam? Just because you think the edge of the foot is 1/4" could be wrong. Get a ruler and measure from the needle to the edge of the foot. Lower the needle to the ruler and look at the line it lands on. Adjust your needle to make 1/4" from there. It take practice to sew 1/4". Good Luck.