Art and Design A comprehensive guide for creative artists - Aaltodoc

This is an
example of a
bonfire kiln,
showing unfired
clay sculpture
and pottery
ready for firing
in a narrow
ditch—dug in
the ground.
Waste mould
Rich (1988, 512) says, a waste mould “is a
negative mould that has to be broken up
and destroyed or 'wasted' in order to remove
or release the positive cast contained within
its interior ... The advantage of using a waste
mould is that it eliminates the fine lines ...
that result when a piece mould is used.” Also,
“only one positive can be secured.” Clearly,
then, the material used during casting has
got to be hard or strong to avoid a collapse.
As a learner dealing with assignments of art related with
casting, you will realise that mould making and casting is
not for sculpture tasks alone, it can be used in very many
other art fields like pottery, jewellery making and other
multimedia crafts to forge and cast. In that manner, moulds
are made for very many purposes in different ways.
Kilns
The types of kilns used for firing clay are many and they
are differentiated by the ways in which they function. All
kilns burn, bake, or dry sculpture as well as pottery. Digolo
et al (1988, 117) allege, “... some are fired by gas, others by
electricity, wood or oil.”
Here is a table list of notable kiln types:
Wood kiln Coke kiln Electric kiln
Saw dust Bon fire Open fire kiln
Coal kiln Oil kiln Gas kiln
As indicated in the previous paragraphs, the purposes of
kilns are almost identical wherever you go, even though
pottery artists and sculptors have individual ways of using
each existing types.
Fresh sticks and tree barks
Clay sculpture
Pottery
The sizes of kilns and how each type uses energy are to a
large extent different. Thereby, an electric kiln is known to
be the cleanest but it is very expensive to use. Electric kilns
are well liked because sculptors or pottery artists—using
such a kiln do not need constant attention. Even though,
firing clay ware requires a very close attention—watching to
control the process of firing.
In this set of circumstance, our aim shall be centred on
equipping learners with knowledge of firing clay using very
simple methods and at a low cost.
As an example let as make a brief review on how to fire
pottery with a bonfire kiln. If such a kiln is carefully used,
it can burn clay artworks at higher temperatures in the
shortest time possible. It can be lit well by using fuels such
as cow dung, saw dust, brushwood, straw or reeds—spread it
well inside a shallow ditch dug on sloping open ground.
Then, carefully place clay artworks on the well laid 'fuels'
inside the ditch. And then, add more fuels on top. Other
kinds of fuels may include sticks of fire wood, recently
harvested fresh wood and tree barks.
Start the fire, a bonfire kiln can reach high temperatures but
it cannot effectively maintain them. That is to say, watch
as fuels burn and where possible add more or keep on
enforcing the fuels in sufficient amounts when needed for
fire to keep burning.
After burning, wait until when terra cotta (unglazed,
brownish-red earthenware) has cooled down—back at a
fairly low temperature and then remove them from the
bonfire kiln. It is also necessary to clean off some ashes from
them.
Then, take the fired sculpture artworks for display.
Welding sculpture
Welding is a method of joining metal pieces or parts
together to produce a sculpture artwork.
The process of working is done by using electricity (this
is expensive), or by using bottled portable oxyacetylene
welding gases (it is cheap) carrying oxygen and acetylene.
As a matter of safety, during welding wear dark eyeglasses
to protect eyes from extreme bright light caused by welding
fires. Dark eye-glasses and other safety gadgets are as well
necessary even to those watching a welding process.
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