Transcript basic pottery vocab

CLAY VOCABULARY
Wedging
Kneading the clay by
cutting and reforming it in
order to expel air and
blend all the ingredients.
Wedging
Clay Body
 It is possible to work with the clay
as it comes from the earth,
however it will not posses certain
characteristics such as color,
plasticity, strength, or fired density.
By mixing two or more clays and
adding other materials, these
effects can be produced in what is
called a clay body.
Pinch Pot
To make a pinch pot begin with a ball of
clay. Push your thumb into the center,
and then pinch up the walls. Turn the
piece as you pinch. This will help you
keep the walls of the piece at an even
thickness. Lightly push the bottom of the
pot on a flat surface to create a flat spot
that it will rest on when finished.
Pinch Pot
Banding Wheel
Banding Wheel: A
portable turntable for
rotating pottery being
formed, decorated or
otherwise worked
Banding Wheel
Bat
A disk or slab of plaster
or other material such as
wood used for drying
clay for supporting clay
forms while being
worked
Kiln
Kilns are thermally
insulated chambers, or
ovens, in which controlled
temperature regimes are
produced. They are used
to harden the clay body.
Kiln continued…
Kilns can be electric, natural gas, wood, coal,
fuel oil or propane. Materials used to heat the
kiln can affect the work: wood ash can build up
on the surfaces of a piece and form a glaze at
high temperatures. Some potters introduce
chemicals into the kiln to influence the effects of
the firing.
Note: we use electric kilns
Electric Kiln
Coil Pot
Coil Pot - Examples
Coil Pots
 Made from ropes or coils of clay. Layered one
upon another to create the walls of the pot.
Smooth coils or leave some coils exposed.
Scoring
 Scoring clay is the method potters
use to adhere two pieces of clay
together. Simply use any pointed
clay tool to make X shaped marks
into the clay where you will be
adhering another piece. This
roughs up the surface area of the
clay, which is needed for a good
adhesion.
Scoring
Slip
Slip is another name for clay
glue. Slip is simply wet
sticky clay. Slip can be
applied by a paint brush or
simply your finger. Do not
use just water.
Slip
Score and Slip Cleanup
Sgraffito
 Sgraffito. This is a decorating
technique where a colored slip is
applied to a leather-hard piece of
clay and left to dry. Once the slip
is dry a variety of different tools
are used to carve into the clay to
remove the slip and leave an
embedded decoration behind.
Sgraffito
Mishima
A Japanese decorating
method of filling a
design impressed or
carved into the clay
with a different
colored slip.
Mishima: Comparison Example
Sgraffito
on the
Left
Mishima
on the
Right
Crazing

The fine network of small
cracks that occurs on
glazes. The Japanese
encourage crazing and
will stain cracks with
concentrated tea.
Crazing
Raku
Pottery is fired normally but
removed when it is red hot and
the glaze is molten. It is then
usually placed in a bed of
combustible materials and
covered, creating intense
reduction resulting in irregular
surfaces and colors.
Raku-Examples
Slab Building
 Clay slabs are cut to shape and joined
together using scoring and wet clay called
slip. Slabs can be draped over or into forms,
rolled around cylinders or built-up into
geometric forms. Large forms are difficult
because of stresses on the seams and
because the slab naturally sags. Some
potters get around this by working fibers
into the clay body. The fibers burn out
during the firing, leaving a network of tiny
holes.
Slab Boxes
Stages of Clay
The clay goes through stages of drying.
1.Wet, or raw clay.
2. Leather hard
3. Bone Dry
Greenware
Any pottery that has not
been bisque fired. The
clay could be wet, leather
hard, or bone dry.
Greenware-all stages of unfired clay
Leather hard
Clay has begun to dry
out and can no longer
be formed or molded
but the surface can
easily be carved
Leatherhard-can ‘t
continue to remold
but effective carving at this stage
Bone Dry
Clay that has been
completely air dried
and is ready to go to
the first firing
(bisque)
Bone Dry-very brittle at this stage, ready
for the bisque fire
Firing the Clay
There are two firings:
1. Bisque
2. Glaze
Bisque Firing
The first firing, without
over glaze. However
colored under glazes
(slips) may be applied to
the greenware and then
bisque fired.
Bisque firing-load bone dry clay
Glaze Firing
The final firing,
with overglaze.
Glazeware:
to be unloaded
finished glaze firing; ready
Finishing the Pottery
1.Greenware~Underglaze ~ Bisque fire
2. Bisqueware~Clear Overglaze~Glaze fire
OR
1. Bone dry clay~Bisque fire
2. Overglaze applied~Glaze fire
Underglaze
Colored clay slip used
to decorate Greenware
on leather hard pieces
before bisque firing.
Apply underglaze to greenware
Overglaze
A thin coating of glass. An
impervious silicate
coating, which is
developed in clay ware
by the fusion under heat
of inorganic materials.
Overglaze: apply over bisqueware
Grog
Grog is fired clay that has
been crushed into
granules which may be
added to a clay body to
increase strength, control
drying and reduce
shrinkage.
Grog
Pyrometric Cone
 A small triangular pyramid
made of ceramic materials that
are compounded to bend and
melt at specific temperatures.
The cone serves as a timetemperature indicator of heat
work in the kiln.
Hand-building
Wheel Thrown