All of the door framing must be made and assembled first so you know the exact measurements needed for the widths and lengths of all the panels including the dimensions for the arched panel tops. This is true for all doors, raised panel walls and wainscoting including furniture, all the time in every historic house in existence. The feather edges on my panels are 1 5/8" wide, which leaves a 1 1/8" reveal, minimum. The picture above shows the drawing of the arch on the field which is 1 5/8" away from the shaped end. Now I score the pencil line carefully with a scoring knife (it is a particular carvers knife) so I can carve the shape using a 1 1/4" wide straight and a 45* angle chisel to match the profile. >