PINCHED
BURNISHED
BIRD
Quic kTime™ and a
TIFF (Unc ompres sed) dec ompres sor
are needed to see this pic ture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Working with simplified form.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Quic kT i me™ and a
T IFF (Unc ompres s ed) dec ompres s or
are needed t o s ee thi s pi c ture.
QuickTi me™ and a
TIFF ( Uncompressed) decompressor
are needed to see thi s pi ctur e.
Studio Procedures
Lockers
Available on a first come first served basis.
Sign up with a partner. Check locker first.
Clay is available for purchase.
X
Recycle= $3.50 Earthenware = $6.50 Stoneware = $6.50 Porcelain $7.50
We use one cone 6 terracotta
and everything else is cone 10.
NO LOWFIRE CLAY
Getting Started
With
Clay
What is clay? How is it different than just dirt?
Al2O3 2SiO2 2H2O
Clay Origins
Clay
is decomposed granite.The
closer to the source, the purer
the clay. Kaolin, the main
ingredient of porcelain is the
purest known clay. Earthenware
has the lowest melting point, it
has journeyed the furthest.
Clay Properties
• Plasticity – the
property of being able
to be molded and retain
shape,slippery
• Shrinkage – cracks
as it shrinks
• Refractory – resists
melting, resists acid
• Transforms – heat
chemicals changes
into permanent shape
• Plasticity – Ball clays
most plastic
• Shrinkage – Grog,
sand or temper is
added to reduce
shrinkage & cracking
• Refractory – many
earthenwares will melt
• Transformation – clay
becomes permanent
around 1000deg
during bisque (porous)
Categories of Clay Bodies
• Earthenware – low fire, porous, grey-red
terracotta (cone 6)
• Stoneware – mid to high fire, many colors
buff, b-mix, stout, 612, S. Barbara
• Porcelain – most refractory, resistant to
acid, whitest (colors look best on)
glacia, pier, coleman
The difference between stoneware, porcelain, earthenware.
Temperature (melting point)
Texture (grog, sand)
Ingredients (flux, temper, colorant)
Color
• Which is which: Glacia, B-Mix, Buff,Terracotta, Stout…
Safety Reminders
• Wear appropriate clothing
• Minimize toxic exposure
– Use gloves or stir sticks
• Dust is the enemy.
– Use a mask
– Work in a well ventilated area (outside)
– Minimize (sand on paper, toss whole thing)
– Wet sponge as often as possible
Techniques for successful throwing.
• 1) Clay prep
• A) Moisture – not too wet, not too dry
• B) Wedging – even distribution of particles
•
•
•
•
2) Centering
3) Appropriate speed control
4) Knowing what shape you want
5) Finishing piece in timely fashion
What is a pyrometric cone?
Rank coolest to hottest -- 6, 06, 10, 04
At what cone do we:
bisque
mid-range
raku
high-fire?
2) Creating Form and Surface
• Form is the shape of an object, including its
internal space, surrounding space and negative
space. Negative space is the space between
solid shapes.
• The subject of the form may be abstract,
realistic, functional/utilitarian, non-functional,
vessel or sculpture.
• Surface treatments include texture, oxide, slip
designs, and glaze/no glaze.