Melt at 2200ºF (1204ºC) in 25 pound charges. Wait until surface has leveled off, then charge again. Soak at 2100º to 2200 F (1144 to 1204ºC) for 2 or more hours. Ramp down as slow as your scheduling permits to your desired working temperature. Common working temperatures are 2075º to 2125ºF (1135 to 1163ºC).

“Squeezing” the glass 50 to 100 degrees below working temp will help facilitate a seed-free melt.

(Different furnace types and sizes will use different procedures. Many blowers charge and soak at lower temperatures; turnover time will then be longer).