Pottery Unit

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Art I Pottery Unit
A. Tools
1. Sponge (elephant ear)
2. Needle
3. Clay cutter
4. Rib
5. Loop
6. Trim tool
7. Cutting Knife
8. Banding Wheel
B. General hints:
1. Make no shortcuts in preparation and construction of your pots. Air bubbles, uneven
walls, poor scoring of joints and excessive handling will wipe out 50% of the pots constructed.
2. Preserve with plastic. Drying too fast can cause cracks.
3. Allow for shrinkage.
4. Never enclose totally without an air hole or BOOM.
5. Rule of Thumb: Thickness ¼” – ¾”.
6. Bottom of project should be free of glaze.
7. Touch no one’s work but your own!
8. Put your name on all work.
9. Clean tools and put them back where they belong.
C. Terms
1. Clay: Decomposed granite-type rock free from decayed vegetable matter.
2. Ceramics: Objects made form fired clay. Also known as pottery.
3. Kiln: Furnace for firing ceramic products.
4. Wedging: Working clay on a table to force air holes out.
5. Kneading: Working the clay with the heel of your hand for consistency.
6. Joining: Connecting separate pieces of clay.
7. Score: Scrape or scratch slight grooves into area to be joined.
8. Throwing: Forming pottery using moist clay on a potter’s wheel.
9. Handbuilding.: Forming pottery without using a potter’s wheel.
Pinch, Coil, Chunk, Slab or Combination of these.
D. Progression of clay from beginning to end product.
1. Dry: Clay that has been mined, pulverized, screened and is sold in bags.
2. Slip (Clay Glue): Soupy stage immediately after mixing with water. Used to join pieces together.
3. Moist (wet): Clay that has had water added to it and is moveable and very workable.
4. Plastic: Clay wet enough to bend without cracking, won’t stick to tools
(to remain this way: store with a wet rag and under plastic)
5. Leatherhard: Clay that is moist but has dried some and becomes rigid. It is cold to touch because of
the moisture still in it. You can carve into this but it is fragile and brittle.
It can be dented and bent slightly.
6. Bone dry: Completely dry. Water has evaporated. It is no longer cool to the touch.
It will be lighter in color and VERY FRAGILE!
To get to this stage, dry a few days with plastic “bonnet” over it.
7. Greenware: Clay pieces that have never been fired.
8. Bisqueware: Unglazed piece that has been fired once.
9. Glazeware: Bisque piece that is glazed and fired again.
E. Decorating the form: The surface concept completes the project.
1. Glaze: A liquid made from finely ground minerals that when applied to a pot and fired at a
temperature to mature the glaze it will form a glass-like surface on the pot.
Finishes range from dull or matt to shiny.
a. Defects in glazes:
Crawling: glaze doesn’t stick because clay was too dusty or too much
glaze was used
Peeling: glaze separates from clay body because pot was dusty.
Blisters: All glazes go through a period of fusing when some gases escape
through bubbling on the molten glaze. A kiln cooling rapidly will
not allow some glaze time enough to smooth out.
Runny Glaze: Glaze will pool on the bottom of a project if a low temperature glaze is
used on a high temperature clay and then fired to a high temperature.
b. Methods of glazing:
Pouring: Thin creamy glaze poured inside the pot. Shake it upside down to remove
excess glaze. Place on a rack upside down and pour glaze on the outside.
Dipping: Dip the pot into a bucket of glaze, turning until glaze covers it.
One side may be dipped at one time. Touch up with a brush.
Brushing: Use a large soft brush. You can thin your glaze and pour the inside first. Brush
with thicker glaze. Use a fully loaded brush for each stroke. Go around the piece once
and then repeat. Use 2-3 coats or until the glaze appears even (no thick and thin areas).
Spraying: Use a thin mixture with a power sprayer or a hand sprayer. Keep the sprayer at
right angles to the surface. If you hold it too close, it will run. Spray until an even
thickness about 1/16” thick.
2. Texture: May be applied or carved.
3. Incised: Cutting into the pottery but not all the way through. Done when clay is leatherhard.
4. Pierced: Cutting complete areas out or away from the pottery. Done when clay is leatherhad.
5. Wax resist: Applying wax in a design on the pottery to prevent glaze from adhering.
Assignment #1 – Pinch Pot
Make a bowl, basket or mug using the Pinch pot handbuilding method.
Decorate the surface with incised design or texture.
Assignment #2 - Coil Project
Make a bowl or vase using the Coil method of handbuilding.
Incorporate design within the coils or by applying decorative coils.
Hints: Score and add slip to join.
Smooth the inside
Cover small parts with wet towels while it drys.
Cover with plastic while to dries so it doesn’t dry too fast. (may cause cracking)
Assignment #3 - Slab Project
Make a box, basket, candle holder or bowl using the Slab handbuilding method.
Decorate the surface or pierce it with design.
Hints:
Score and slip slabs together. Add a reinforcement coil on the inside at each joint.
Challenge Assignment: Combination of Handbuilt methods. Allow for addition of other materials such as
yarn, reed, pipe cleaners, etc.
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