I use a very old method to mark my quilt if I'm doing the baptist fan. I have a pencil on a string. I hold one end firmly in place and draw the fan by pulling the pencil the distance I want the lines apart and draw an arc. I mark as many arcs as I want( a6-9) then move the string to the outside line edge straight across from the starting point and begin the arcs again. I have tied small knots in the string so I get even distances between the lines at times. The pencil has always washed out. If I was afraid it wouldn't, now I use frixion pens and have had no problem with them not washing out.