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A stream of molten glass, at its plastic temperature (1050°C-1200°C), is cut with a shearing blade to form a cylinder of glass, called a gob. The process starts with the gob falling, by gravity, and guided into the blank moulds, two halves that are clamped shut. Akarigar blows air into the hollow pipe from the other end to make the glass take the shape of the mould. Water is sprinkled over the mould to cool it off after every piece. The vessel is then picked up from the mould and kept to cool. As glass cools, it shrinks and solidifies. Uneven cooling causes weak glass due to stress and break. For even cooling, these are kept into an annealing oven that heats the container to about 580°C then cools it. Similar process is followed for making plates too but the only difference is that air is not blown into the pipe to make the plate take the shape of the mould. Molten glass is pressed in between two metallic die plates.
