Rafter tails are not my favorite part of paper modeling. Decided to try another approach & use paper matches. The matches I found measured about .130" about 6.24 in O scale. Also about .040 thick. ( 1.92" ) in O scale....about right. I model mostly in HO, so I sliced them down to about .09, which is about 7.75 in HO..acceptable. Cut the angle on the end that fits the wall & roof of the structure & glue in place. After the glue dries, cut them off with a flush cutter even with the edge of the roof & parallel to the building side. Mine had a gray / brown color that worked well.
Scott