Chapter Three
PREPARING THE CLAY
In this section we will introduce some common methods of clay preparation. These are:
• dry grinding
• pit soaking
• the "Keyo method"
Remember, however, that one of the best ways to find out how clay is prepared in your area is to ask local
potters.
Dry grinding
The clay is dug out, dry or wet, then broken up into small pieces and dried thoroughly. When dry, it is
ground to a fine powder. Traditionally, this is done using a grinding stone. The clay powder can then be
mixed with the correct quantity of fine sieved sand. The correct mix will depend on the type of clay. Then
water is added carefully to form a workable
clay. The clay is wrapped in polythene and left
to rest for two to three weeks. This method is
advantageous in that stones and lumps are
removed or ground up. Manual grinding is slow
and labour intensive. In addition; the dust
produced is dangerous if breathed in. Since
the stove liners use quite large quantities of
clay, manual grinding is not especially suitable
for stove production.
Fig. 3.1 Dry grinding clay
Pit soaking
The clay is dug out, dry or wet, and broken up into small pieces, then dried thoroughly. It is mixed with a
lot of water so that it dissolves. This mixture can be sieved to remove stones, then allowed to soak in a
brick-lined pit. When the clay has broken down
and settled, excess water is drained off,
evaporated or allowed to soak away. When the
clay is sufficiently dry to handle, sand can be
mixed in the right proportion. The correct mix
will depend on the type of clay. The clay is then
wrapped in polythene and left to rest. This
method can be used to prepare large quantities
of clay, though building enough pits can be
costly. The clay can be soaked in an old oil
drum. Excess water can be taken off when the
clay has settled, and the clay can be tipped
onto sacks to dry out.
F
Fig. 3.2 Pit soaking clay