Many years ago when I would go to quilting club with my mother, the ladies quilted baptist fans using a template my father had made. He took a piece of plexi glass about 12" or more long (can't remember that far back) and about 2-3" wide then he drilled holes in it the distance apart my mon wanted. To use it she put a tack or something like that in the hole in the end, then put a pencil in each hole drawing the arc where she wanted. She was way ahead of her time. Sure do miss her.