Well, as funny as this might sound. If I needed to turn out scrolls like that, I would take a peice of flat plate, the starting thickness of the last biggest part of the scroll, and then forge it into a taper matching the exact taper(or dang close) to the taper in the negativespace. then you would just curl up the flat peice of tapered to match plate right inside of the scroll or freehand into another perfect scroll again, and bam, all you would have to do is taper the square or round right and insert it into the flat bar scroll.