Originally Posted by
Tartan
If I am understanding the question right, you are trying to iron over a smooth 1/4 inch curve on the sections? I would make myself a thin cardboard (white bristolboard)shape of the piece (1/4 inch smaller) and use it to iron the edge over. Ideally you could find a piece of heat resistant template plastic to make the shape from but thin cardboard will work.
This is a great idea, thanks for sharing.