Mode Zero

As a production engineer, I would have thought that the finished was achieved after cold rolling the ali sheet to thickness, then passing it under a row of rotating fine wire brushes or polishing mops spaced on a mandrel to abrade the surface lightly, probably two passes, one each direction and offset to achieve the grain effect. Just my two penneth worth, but would start with that process to achieve the consistency. Once "striped", it would be lacquered to stop oxidation of the abraded surface.....