I've never heard of a fan design frame either. Am most curious.
I primarily quilt on a Grace Z-44. It has 4 rails & there is no basting of any kind to do. One rail for batting, one rail for backing, one rail for top & then the front rail where they all come together.
I also have a Grace portable floor frame & also a lap frame ,by Grace, also. (I oughta be paid a commision by those folks as much as I advertise for them! :mrgreen: )
Riley
This is the Z-44, nicknamed Mrs. Grace