I was fortunate enough to get a box of feet that had a 1/4" foot for my FW. It sews a great scant 1/4". I purchased a 1/4 w/guide for my Viking and although the foot measured correctly, my seams were larger than 1/4" with that one as well. The scant setting on that machine is perfect. Otherwise I used to use a magnetic seam guide on my old mechanical machine or painters tape. I find the magnetic guide (or one you screw to the bed of the machine) more accurate unless you're using a pile of sticky something.