Page 43 - Curriculum Visions Dynamic Book

the stages that a
glassblower might
go through. That is,
you need to get the
ingredients necessary
for glass, you need to mix
them, then heat them in a furnace,
and then you need to shape them and finally slowly cool the finished articles.
Mass production works best if the raw material arrives in a steady stream. In this case the raw material is molten glass, and it is pushed out through a nozzle of the furnace (it is extruded) like toothpaste from a tube.
1. Containers
Containers such as bottles and light bulbs have to be made singly. As a result, the glass flow has to be changed so that small, precisely measured pieces, or gobs, of glass are fed into the shaping machines.
The shaping machines are essentially complicated moulds. The glass is blown to shape once it is inside the mould.
Different objects require different- sized gobs of glass. This amount of glass is decided by setting the time interval for giant shears to cut the glass into pieces.
The cutting is arranged to coincide
with the arrival of a mould. The gob of
glass falls into the mould and is either pressed or blown into shape depending on which article is needed. Fantastic speeds can be achieved by some modern machines.
(Above) Gob of glass falling into the mould before being blown into shape.
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