Modifications to a pottery wheel
Practical Action
Slip casting is similar to metal casting. Clay in liquid state (casting slip) is poured into a dry
Plaster of Paris mould in which the water of the clay paste is absorbed by the Plaster of Paris
leaving a coating of clay in the mould.
Pottery Wheels:
Potters are characterised by the throwing wheel they use
in the throwing process. Potters' wheels were recorded to
have been in existence in Central Asia by 3,500 B.C., in
Egypt by around 3,200 B.C., and in Crete 3,000 B.C. The
earliest form of the throwing wheel was a rough horizontal
circular table turned on a pivot very close to the ground.
Another variation was a wheel similar to a cartwheel (with
spokes) placed horizontally and turned on a pivot with the
help of a long pole inserted into a socket of the wheel
(figure 1) the Indian wheel.
Chinese/Japanese handwheels had a heavy wooden disc
mounted on a porcelain cup. The potter imparts energy to
the wheel by rotating the disc vigorously with the help of a
short stick inserted in a hole on the disc (figure 2) the
Chinese/Japanese handwheel.
Figure 1: Indian Wheel
An improvement to this wheel was made when the
work table was raised up to enable the potter to
sit comfortably at work, while he imparted
momentum to another wheel below, attached to
the work table, by kicking it (lower wheel) with his
foot. This kickwheel is sometimes referred to as
the German wheel (figure 3).
An attempt to transfer kicking of the wheel to a
pedal action was made in the St. Ives kickwheel.
In this wheel a cranked spindle connecting the
worktable to the inertia wheel was linked to a bar,
the kicking of which imparted rotary motion to the
inertia wheel (figure 4) St. Ives Kickwheel.
The modern potter's wheel has the drive through a
friction clutch connected to an electric motor.
The Criteria Demanded in the Modification:
The essential requirements of a potter's wheel
are:-
a flat circular disc to rotate about a
vertical axis forming a rotating worktable.
the worktable continuing to rotate while
the potter forms the article using his
hands, during which time his feet should
remain idle.
if any energy impartation is required from
the potter, it should be through the use of
his legs only.
The modification finally demanded a kickwheel
suitable for operation by rural female operators.
Figure 2: Chinese Handwheel
Figure 3: German Kickwheel
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