20.5-Inch-Mirror-Blank-Project

Originally I started with a 16 inch circular cutout mirror blank. Circular is a bad choice due to concentrating stress in the narrowest part of the webbing. The 20.5 inch casting was designed with a hexagonal webbing. The photo on the right shows the general layout. The original autocad dwg file is here: Media:20.5-Hex-Pattern-Layout.ogg