"First thing you will need is a former to create the curve. I made one up from balsa wood and mounting board, with regular sections to keep it's shape. "
Trying to figure out how you did this Richie, did you use strips of balsa to make the roof former and then sand it down?
"This method also works for longer coach roofs, but is trickier generally"
What difficulties did you encounter with the longer roof lengths?