Art I: Intro to Ceramics

Printable Vocabulary Sheet

Classroom Rules

Clay Vocabulary

Ceramics: pottery or clay sculpture fired at high temperatures in a kiln to make them harder and stronger.

Kiln: A specially designed oven capable of reaching temperatures over 2000 degrees F (can be gas, electric, or wood-fired)

Clay: moist, sticky dirt (mug) composed of fine-grained minerals, which can be shaped when wet and hardened when dried or heated (rock material)

Tools: mainly used to shape clay

Types of Clay

Earthenware (1800-2100 degrees F): clay fired at low temps, often contains iron and has a porous surface when fired.
Stoneware (2200-2400 degrees F): a buff, gray or brown clay which is heavy, opaque, and highly plastic in nature with a high firing temperature.
Porcelain (2200-2550 degrees F): a very fine white clay with a high firing temperature, non-porous, strong, and translucent when fired.

Tools

Hands, Loop Tools, Modeling Tools, Ribs, Sponge, Wire Clay Cutter

Wheel Throwing

forming pottery using a wheel powered by a foot, a stick, or an electronic motor

Slip Casting

a method of creating pottery using molds to reproduce forms

Hand-building Techniques

Pinch Method: fundamental to manipulating clay, pressing the thumb into a ball of clay and drawing the clay out into a pot by repeatedly squeezing the clay between the thumb and fingers
Coil Method: long, snake-like ropes of clay that are used in making pottery; involves building the walls of a form with a series of coils into the required shape; surface can remain coil-textured or they can be smoothed
Slab Method: a form is built up by joining shapes cut from thick sheets of damp clay

Decorating Methods

Glaze: a glass coating that is especially made to stick onto ceramic surfaces
Underglaze: colored slips applied beneath a glaze layer
Stain: raw pigments, can be water or acrylic based
Burnishing: rearranging and compressing clay particles by rubbing the surface of a clay object until it becomes glossy

Stages of Clay:

Greenware: clay that has not been fired and still able to be made back into mud and recycled to use again.

Stages of Greenware

Slip – wet and soupy
Plastic – moldable without cracks
Leatherhard – clay is dry enough to maintain form and wet enough to be smoothed, carved, and added to.
Bone dry – clay has dried as much as possible before first firing and is extremely brittle. Clay is most fragile at this point!

Bisqueware: first firing where all remaining water molecules are released from the clay transforming it into ceramic (Why are air bubbles dangerous during a bisque fire?)

Glazeware: second firing where glaze has melted into the ceramic surface making it non-porous

Score, Slip, and Seal

When joining two pieces of clay, you must always remember the 3 S’s.
Score: roughening up the surface of the clay to act like Velcro
Slip: liquid clay or water used as “glue” for attaching
Seal: to press the pieces of clay firmly together where they are joined

Clean-up

Hazards of clay dust: silica particles = EXTREMELY tiny pieces of glass, which become airborne easily and inhaled – extremely hazardous to lungs!
Solution: WET clean-up prevents dust from building up and becoming airborne. Use wet sponges, spray bottles, wet rags

Ceramic Wheel Thrown and Stamped Mugs

Throwing mugs on the wheel has become an obsession of mine lately. I love the process of throwing on the wheel and trying to perfect the shape of each mug. Every time I pull a mug, I get better.

Along the way, I have discovered a few tools to help out the process and make it easier to reach my goal: beautiful thrown mugs that people will treasure and love to hold in their hands with their favorite hot tea, soup, or cup of joe.

Here are some of my favorite tools to use while throwing mugs.

A bat for the wheel head

Bat

This nifty PVC pipe tool for opening a ball of clay

Ball Opener

A sponge to clean out the inside

sponge

A “metal rib of death” to clean off the slip from the outside when I’m done throwing and shaping

metal rib

A wooden undercut tool to scrap off the skirt and the excess clay at the bottom of the pot

wooden tool

A fishing line attached to two large washers to cut the mug off the wheel

fishing line tool

A feather tool to score the mug to attach the handle

feather tool

A scoring rib to score the handles

scoring rib

A paintbrush to paint on the slip to attach the handles

paintbrush

These awesome stamps from my Ceramic Stamps post to add texture to the mugs

ceramic stamps

These trimming loop tools

trimming tools

A Sherrill Soft Rib to smooth out the pots after trimming

sherrill rib

My newly made extruder for handles

handmade extruder

It takes a few days to complete the mugs. I throw at least 4 at a time, leave them attached to a bat, and set them out to dry for a few hours depending on humidity. Then I wrap them in plastic (I cut open a tall kitchen trash bag to drape over all of them at once) so they won’t dry out completely overnight and let them sit until the next day.

freshly thrown mugs on bat

If they are still too damp the next day, I uncover them and keep an eye on them until my fingers no longer leave prints when I touch it. If they are still too squishy, I let them sit in lightly wrapped plastic another day. Once they are stiff, but not dry, I can stamp them. I put them back on the wheel, and it’s easy because they are still attached to the bat. Then I can turn the wheel as I go to stamp around. Always support the opposite side with a finger or two while stamping. If the clay comes off or sticks to the stamp, then it is still too wet to stamp. Once I’m done stamping, I cut them off the wheel and set them under plastic for another day.

stamped mugs

In the meantime, I pull or extrude handles and place inside my magic box to firm up while I finish the mugs.

extruded handles

The next day, I check for stiffness. They need to be leather hard to trim. It’s fine if they are a little past leather hard, but not too much because one does not want to create clay dust! That is dangerous stuff to breathe in. Over time it can build up in the lungs and cause scarring and damage. If they are leather hard, I flip them over, center them again on the wheel by tapping into center, and keep them in place with at least 3 thick coils of soft clay. Then I use the trimming tools to trim a foot and trim off any excess clay making my mug too heavy. I want to make the walls even thickness. After I’m finishing trimming, I set them aside still upside down because the foot is now the softest part of the mug, and wrap them loosely under plastic to firm up.

trimmed pots

Once the bottoms and handles are leather hard, I can score, slip, and seal the handles onto the mugs to complete them. I leave them upside down and sign the bottoms and wrap them loosely with plastic to sit for a day, then I can place out to dry completely right side up. If I allow them to dry too fast, they might crack. Once they are completely dry with no moisture whatsoever they are called Bone Dry Greenware.

mugs drying

When they are bone dry, I can scrape off any burrs from my signature on the bottom or the stamping around the sides and place inside a kiln to fire to cone 04. Once fired, they become bisque ware. Then I can paint, dip, or pour the glaze onto the mugs and fire again. I like using cone 6 glazes because the mugs become more solid the higher you fire them, and cone 6 is a medium fire which ensures these mugs will not break easily. I will most definitely want to use a glaze that breaks over the edges to emphasize the texture.

finished mugs

Ceramic Handmade Tools

You, yes YOU, will be making some tools this year! They are super easy, and super handy, and SUPER cheap! Yay! We love saving money, right? Here are a few things for you to start looking for NOW:

  • wooden sticks (about finger thickness, but can be thin or thick depending how how strong the wood is)
  • plastic bottles, milk jugs, plastic backing on used spiral notebooks, old credit cards or gift cards or school IDs, any kind of stiff plastic that won’t easily bend or break
  • floss
  • hot glue gun and hot gun glue sticks
  • wire coat hangers
  • small hacksaw blades
  • wood scraps
  • string, twine, any kind of thick-ish rope-like stuff
  • paper clips
  • electrical tape
  • PVC schedule 40 pipe and connectors
  • Gorilla Glue

handmade tools

These are tools I made out of the some of the items I listed above.  They were quick and easy and came in handy when I work on my ceramic projects.

The board covered in twine can be pressed against clay to form a cool texture. The carving tools above are good for sgraffito or scraping away a top layer of underglaze to reveal the raw clay beneath. The central blue tool I cut from a water bottle and cut triangles out around the edges which is great for scoring the clay when joining two pieces together. The hacksaw blades I bent and taped together with blue electrical tape, and they are good for trimming or creating lines in leather hard clay. The paperclips I straightened and then bent in half and taped together at the bottom with black electrical tape to form great texture or scoring tools.

I had to spend a little money for this one, but it was not much. I made this tool out of schedule 40 1/2″ PVC pipe, a 1/2″ T connector and two 1/2″ elbow connectors, along with some PVC glue. It will open a ball of clay so that the bottom is 1/2″ thick and will also compress the clay so that it does not get the famous “S-crack”. I used the tutorial listed below in the links section for making a Simple Ball Opener.

Ball Opener

Requirements:

  • Create 4 tools to use with the clay.
  1. Wire cutters – out of fishing line and clay
  2. Needle tool – out of coat hangers and clay
  3. Texture tool – out of paper clips and electrical tape or plastic
  4. Smoothing tool – out of plastic
  5. Optional: Sgraffito tool out of wooden sticks, floss, hot glue, and measuring tape
  • Use recycled or found objects. Do not spend money on this if you don’t have to.
  • Photograph your found/recycled objects for a before picture and then once you’ve made your tools, photograph an after picture and post them to your blog in one single post.
Here are some links to also help you when you are making your own clay tools:
Ms. Long's Pinterest Ceramic Tools Board
Simple Ball Opener - Great tool for throwing!
How to Make Clay Tools the Economic Way
Homemade Pottery Brushes
Making Potters Tools - Youtube Video
Simple Sharp Sgraffito Tools