I tried again with french vanilla, white, medium amber, and clear and weighed just about 1700 gms. I had a “stopper” in the dam so that I would have a hole in the glass (3.5 inches in a 12 inch dam) which I later filled with a piece made with murrini. 500-1700-2hrs, full-1500-1 hr, full-900-3hrs, 100-800-0, 200-700-0, 300-100-stop. I have a beautiful piece of glass although the stainless steel dam was warped. I re-fired at a full fuse with the extra piece, and although the edges need a lot of coldworking, the end result is more than I hoped for.