Pat I too am a new owner of a Janome 6600 and had to take my machine back to the shop to get the dual feed off, you pull down and back and up on it and it will release, on page 13 of your manual is the instructions. Then to change the foot just unscrew the the thumb screw and release the dual feed foot. We have a very good 1/4 inch foot, there is a guide which helps youto have exact 1/4 inch. Good luck Janey