Video showing the making of a 3 foot diameter rondel, by Skeels Glass.
via keithorr YouTube Channel
part 1 - gathering and forming a bubble (3:18)
part 2 - the rondel takes shape and is lifted off (5:26)
text from the YouTube page -
Total working time was 3 hours per rondel.
Rondels were either 36 inch (70 pounds) or 48 inch (105 pounds) with a thickness from 4 inches at the center nub to 3/4 inch at the edge. Rondels were made over-sized and trimmed to diameter using standard glass cutter and large breaking pliers.
Rondels made one layer of a dual glazed unit. Finished units are installed in the Mount Timpanogos Utah Temple of the Church of Latter Day Saints.