Have used the Crayola fine line washable pens for years. Just be sure you are using Crayola. Picked up another brand by mistake and it was hard to get out. With the Crayola, I just wash the quilt after I am finished quilting and all goes away. Just need to follow the directions on the package as to washing. Don't remember any particular color that gave me any trouble. Maybe it makes a difference if they have been sitting on the shelf for a while. Or the weather?, humidity vs dry areas, etc? Usually buy a new box when school starts and they are cheap.