I struggled with this same problem for years. However, I now have two Janome machines, a 720 Jem and a Memory Craft 6600. the needle position is moved using the stitch width, either widening or narrowing it. I use my regular foot and adjust the Memory Craft stitch width to 6.8. makes a perfect scant 1/4" using the edge of the foot as your guide. Best solution I have found.