I have a Viking with a 1/4 in setting and it is still to big so have to adjust to a 3 on my setting button.
I also found that several different width seams all measure 1/4 in on a ruler so you cant go by that its just such a small amount that it dosnt show up on a thick ruler.
You just have to make a block and keep adjusting till it comes out the right size.

What I did to make sure my main & class machine were the same was to use the index card. My main Pfaff 7570 with the 1/4" guide foot makes a perfect 1/4" stitch. My class machine, Kenmore 385.1915 does not have a 1/4" foot. On the straight stitch foot it does have a 1/4" mark, but I have a hard time following it. I used the index card, moved the needle over to 6.0 so my fabric would line up on the right edge of the presser foot. Put a note on my machine, so I would remember. Now I can switch between machines for a consistant stitch. I also am now using serger thread in both machines. Serger thread is a little thinner than regular thread. I haven't measured any seams, but at least they are consistant! Works for me :thumbup:

A very valuable lesson learned the hard way!! Sorry, I'm glad my DM told me right off the bat that all machines aren't the same and use the same machine & ruler for each project! I think she learned the hard way too and didn't want me to go thru it!

This problem is exactly why I mark my 1/4" seam with painters tape on my machines. I don't rely on 1/4" feet or the markings on the machine!

wow, this is an awesome thread with lots of comments, thanks for sharing