Surface Decoration
Design techniques used to put on the
surface of the pottery.
Slip
Oxides
Glaze
Embossed
Incised
Wax on wet
Altered from the wheel
Slip
How to apply slip
• Colored slip is intended to add color to a pot by using the
color of the slip and the color of the clay as well. The
colors of the slip will turn their true color only after the
glaze fire.
• The slip must be the texture of chocolate pudding or a
heavy cream.
• Slip must be applied on wet to leather hard clay. If put on
dry clay the wetness of the slip applied to bone dry clay
could lead to cracking.
• Materials used to apply slip:
– Brushes – brushes don’t hold much slip, however if you want a
brushed or painted look, or you are brushing over large areas of
the pot, brushes will work.
– Slip trailers – a bottle or syringe. These will hold larger amounts
of slip and allow for smoother flowing lines.
How to apply slip – Resist shapes
• RESIST SHAPES – place the
paper shape on the wet pot and
smooth it over to release any
trapped air. Pay particular attention
to the edges of your shape.
Sponge or brush a layer of colored
slip onto your pot, be careful not to
disturb the paper shape.
• Take the paper shapes
off when the slip loses
its wet, shiny, sheen. If
you remove them too
soon the design will smudge.
How to apply slip – using stencils
• Patterns are cut from
paper or contact
paper. The patterns
or designs are placed
on the leather hard
pot. The slip is then
brushed over the
stencil. The stencil is
then peeled away to
reveal the design.
How to apply slip – with wax resist
• Brush liquid wax on the
surface of your clay. Clay
should be wet/leather
hard. Create a design
using the wax. When the
design is complete gently
brush the colored slip
over the design. The wax
will burn away in the
bisque fire. The design
left under the wax will
retain the color of the
clay.
How to apply slip – painting it on
• Slip is directly painted on the
leather hard pot using a brush.
Slip should be applied with a
fully-charged brush and in
successive thin coats (as
opposed to single-stroke built
up-or thick- brush patterns).
– A thin application of slip
may be partially dissolved if
a transparent glaze is used
over it. A very thick coating
may crack or even peel off
the pot, even though it
“appears” perfect after
application.
How to apply slip – slip trailing
• Pour slip into a syringe or
plastic squeeze bottle.
The slip is then squeezed
through the tube onto the
surface of the clay. The
clay should be leather
hard.
– If the clay or the slip is too
wet the line created by the
trailing could bleed.
– If the slip is not a smooth
runny texture (the
consistency of cottage
cheese) it could clog the
tube and come out
unevenly.
How to apply slip - sgraffito
• Sgraffito depends on the strong value contrast of
the slip color to the color of the clay body. The slip
is painted on the entire surface of the leather hard
clay. When the slip dries (with in a few minutes) a
sharp tool is used to scratch a design through the
coating to the clay body beneath.
How to apply slip – the opposite of
sgraffito
• In the leather hard clay carve
a pattern. The carving should
be about 3 cm wide. Fill in
the carved space or grooves
with a slip trailer. Let the slip
dry – until it loses its shine.
Then take a bendable metal
rib and gently scrape away
the raised surface of the slip.
So the slip that remains will
be flush with the level of the
clay surface. As you scrape
be careful not to pull the slip
out of the grooves.
How to apply slip – slip combing
•
•
•
•
•
•
This requires patience and practice.
The clay should be a flat form (plates,
tiles.)
The surface is to be flooded with the
slip-hold the clay at an angle and pour
the slip over it.
Lines of a different color slip are then
applied over the wet slip.
While the lines are still wet and shiny a
comb from which teeth have been
removed (so every 3rd or 4th tooth
remains) is drawn lightly through the
lines across the surface.
More complex patterns can be
achieved by drawing the comb across
a second time, parallel to the first but
in the opposite direction.
Oxide
How to apply oxides
• APPLY OXIDES VERY,
VERY THIN. Do not paint
them on like glaze.
• Oxides can be brushed
on textured surfaces and
wiped with a sponge so
the grooves retain the
oxide.
• Oxides can be painted on
thinly like a watercolor
painting, then you may
put a clear (Clear Bright
NOT Clear Matt) glaze
over them using a
sponge.
Glaze
How to apply glaze
• The glaze should be thoroughly mixed before
using. The consistency should be that of a heavy
cream.
• Rinse your bisque piece under water to get the
dust from the kiln off. This dust can create little
bubbles in the final firing on the surface of your
pot if not removed.
• Glaze can be applied by:
– Brushing (apply two coats)
– Dipping or Pouring (dip once and do it QUICK)
How to apply glaze - Brushing
• Brushing the glaze on tends to be slightly thicker. There is
more gum in the glaze to help it stick to the pot.
• Be careful not to trap small pockets of air under heavy
layers of glaze. These can cause little pin prick holes in the
fired glaze.
• When glazing a pattern you can draw the pattern on with
pencil. Draw soft lines, these lines will disappear during the
firings. When glazing these patterns be careful not overlap
the edges. Treat the glazes like crayons in a coloring book.
Glaze up to the line leaving a small needle tool thin line
in between the glazes. This line will help the glazes not
bleed into each other. You can also draw or carve the
pattern into the wet clay and then after it is bisque fired you
can glaze in the pattern you’ve carved.
• To get a clean line of glaze around patterns: Thin the glaze
down, use a watercolor brush, apply 3 coats, and use a
steady hand.
Brushing glaze
How to apply glaze - Dipping
• Dipping will give the outside a more even coat
than pouring.
• Work QUICKLY! (if you don’t the glaze will be
too thick and will bubble and crack.)
• Wax the bottom of the pot. Carefully-once the
wax is there it is there forever. Trying to scrape
it away doesn’t work.
• Hold the tip of your pot at an angle. Dip the pot
into the glaze QUICKLY. Swirl the pot around
and pull it out QUICKLY, holding the pot upside
down so the glaze will flow to the top of the pot.
(if you hold it so the glaze drips to the bottom
the glaze will melt and stick your pot to the kiln
shelf.)
• Wipe the glaze off the bottom with a wet
sponge. Take a tool and scrape a straight line
around the bottom edge. If needed scrape a
thin layer of glaze off the thickness at the
bottom so it wont pool and stick the shelf in the
firing.
Dipping in glaze
How to apply glaze – Pouring
• You will need a generous
amount of glaze.
• Work QUICKLY! (if you don’t
the glaze will be too thick and
will bubble and crack.)
• Pour the inside of the pot only
half way. As you pour the
glaze out roll the pot around to
cover the uncovered areas
inside the pot.
• To cover the outside of pots
place them on sticks upside
down over a bowl. Having
waxed the bottom of your pot,
pour the glaze over the outside
of the pot.
Glazing with wax
• Wax will repel the glaze that is put over the top of it and will melt off
during the firing.
• Paint a design with wax on bisque ware very carefully and deliberately.
Can put wax directly on the bisque or glaze and place the wax on top of
the glaze, then put a second coat of glaze over the top of the wax.
• Brush or dip glaze over the top of the wax.
• Gently scrape the beads of glaze off the top of the wax. Do not scrape
off the wax. It could scrape off the glaze from under the wax, and the
glaze underneath will have an uneven coat.
Wax - trouble shooting
• Once the wax is on bisque ware it is there to
stay. Even if you scrape it off, the wax has still
soaked into the clay and will repel anything that
is put over the top of it.
• Only wax the bottom of your pot if you intend to
dip it. You do not need to wax the bottom if
you are brushing glaze on.
• Once the brushes are loaded with drying wax
you will need to rinse them with hot water and
soap. The wax will be applied with cleaner,
smoother lines if there is not excess wax in the
way.
Glazing – trouble shooting
• If the bisqued pot is too wet (from rinsing or pouring the
inside) the outside glaze may not take. The glaze will be
too thin because the pot is wet.
• If the pot is too dry sometimes the glaze will be too thick.
• Work QUICKLY! (if you don’t the glaze will be too thick
and will bubble and crack.)
• When glazing patterns with more than two colors, be
careful not overlap the edges. Treat the glazes like
crayons in a coloring book. Glaze up to the line leaving
a small needle tool thin line in between the glazes.
This line will help the glazes not bleed into each other.
• To get a clean line of glaze around patterns: Thin the
glaze down, use a watercolor brush, apply 3 coats, and
use a steady hand.
Glaze over slip
Embossed
How to apply embossed pieces
• Embossing means to add
pieces onto the surface of
your pot. This is done by
scoring and slipping.
• To create the design you
may mold the piece by
hand. (like the frogs)
• Or use a press mold to
create the piece. (like the
chicken) You can make
your own press mold out
of clay and plaster.
Molds for embossing
• To create a press mold. Make the
design out of clay. Place in a
container. Spray with a spray soap
or slimy substance. Put wet plaster
over the design. Let dry, then
remove the clay. The plaster needs
to be dry enough that when
removing the clay it won’t chip the
design and wet enough that you
can still remove the clay.
• You can also take a block of freshly
poured plaster and carve a design
into it. This is called a sprig.
Embossing – trouble shooting
• When attaching the piece
be careful to not damage
the piece you are adding.
• Make sure there are no
air bubbles trapped under
the piece. If there are air
bubbles the piece will
blow off in the firing.
• Carefully take a modeling
tool and push the outside
edges into the surface of
the pot.
• Clean around the edges
with a modeling tool.
Incised
How to carve incised designs
• INCISING - Incised designs are made by scraping a tool point
across the surface of moist or leather hard clay. When a solid tool is
drawn across the surface the clay pushed aside forms burrs or little
clay crumblies. Scrape these away and re-carve the line. Do this 2-4
times until the clay crumblies are gone and the carved lines are
clean. If the tool is held at an angle the lines will look cleaner.
• CARVING – Best done on clay that is leather hard. It can be done
on bone dry clay but the resistance to the tool is greater and
chipping is more likely to occur.
• PRESSING OR STAMPING – Moist clay is best for using a stamp or
found object to press into the clay creating a pattern. A single stamp
can be used multiple times to create an overall pattern. Because
the clay is soft the back side should be supported when pressing or
stamping the clay. Stamps can be made from wood, plaster, bisqued
fired clay, tools, nails, bolts, keys, screen wire, cloth, leaves, fingers
etc.
Altered from the wheel
How to alter from the wheel
• Altered from the wheel combines wheel thrown and hand
building techniques.
• It is more than making a teapot-where a spout is score
and slipped on. It is more than embossing-where a
design is placed on the surface of the clay. It is more
than carving-where a design is carved through the wall.
• Altered from the wheel is the whole piece. A piece is
thrown on the wheel and the structure of the pot is
changed by manipulating the clay with your hands
– The round rim of a pot can be squared using flat
pieces of wood.
– The pot can be cut and bent. Almost peeled like a
banana skin.
– Two wheel thrown pieces can be cut apart and scored
and slipped together.
Wax on wet
• Let wax dry.
• Wipe clay with a sponge.
This will remove the clay
that is not protected by
the wax.
• Paint wax on leather hard
clay. Your piece should
already be trimmed.
• This process does leave
the clay with a grainy
texture.