Why not use the wide, bottom, edge of a dresden plate template, or one of the other stack and whack type templates. The 30degree simpli-ez works well for a charm square. Just align the bottom line that fits, on mine it is the 8.5 mark and cut the excess. Just remember to cut all patches right side up, you are going to reverse them when you sew. One template, many applications. The stack and whack, 15 degree template works real good for 3" strips just in case you want to make a mini tumbler quilt.