Originally Posted by Candace
Fabric thickness and thread weight affect the 1/4" seam. My Bernina foot is wonderful, but I always do a test as I sometimes have to bump the needle over a spot depending on these things. A 1/4" foot doesn't take these into consideration. You must gauge the fabric and thread thickness.
I love the Bernina 1/4" foot, but I too have to "fudge" the needle depending on the fabric and thread. I think this applies to all quarter-inch feet. I always sew a sample seam to get it just right.