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Education Resources

Here is some great resources! 

 

Lesson Plans - In need of some classroom/workshop lessons? 

Ceramic Education - Lisa Arbuckle does a fantastic job educating people on process and technique.

Ceramic Dictionary- A great dictionary helping refine your verbiage and sound like a pro!

Slip Casting- A quick lesson on how slip casting works, 

Mold Making- A quick lesson on how to make a mold!

Additional Information for teachers:

How much clay do I need?

It depends, on your class size, and projects. 

Rovin clay is ordered in 25lb increments, Standard & Laguna in 50lbs.

A small hand-built project or cup/mug usually takes about 1-2 lbs.  For teachers, determine how many clay projects the students will do and how many students you have. You will likely need about 1.5lbs per student per project. By this measure, for one project, 1 box of clay will provide for around 16 students.

EX: I want to make 12 3lb bowls. 25lbs / 3lb = 8.33 = roughly 7 or 8 bowls per bag if I don’t make any mistakes. I will buy 2 boxes or Rovin clay or 1 box of Laguna clay which will leave me about 4 extra 3lb balls in case I make mistakes.

 

What is the difference between cone 5 and cone 05?

There is a common misconception that cone 05 and 5 are the same temperature. Cone 05 is actually much lower in temperature (1886 degrees F) than cone 5 (2167 F). Think about the ‘0’ as a negative number sign. from lowest temperature to highest temperature the cones would be 05, 04, 03, 02, 01, 1, 2, 3, 4, 5. See Cone Chart here for details on temperature. 

 

What is Bisque, Low-fire, Mid-fire, and High-fire?

A “bisque” firing is the first firing of greenware to a low temperature (typically between cone 06 and 04, 1830 to 1945 degrees Fahrenheit) to harden the clay just enough to apply glaze. This is done when clay pieces are bone dry.

Low-fire” is a glaze firing temperature ranging between cone 06 and cone 04 (yes this is the same temperature as most bisque firings) Typically between 1830- and 1945-degrees Fahrenheit. This is commonly used for earthenware or terra-cotta clays.

Mid-fire” is a glaze firing temperature between cone 5 and cone 6, between 2185 -2232 degrees Fahrenheit (though it can include cone 4 through cone 7.) This is the most popular glaze firing temperature for electric kilns. Clays typically fired at this temp include midrange porcelains and stonewares.

High Fire” is the highest glaze firing temp typically seen used in gas and atmospheric kilns though there are many electric kilns that are capable of this temperature range. High fire encompasses cone 8 through cone 12 though cones 9 and 10 are the most common “high-fire” cones from.

 What is the difference between Glaze and Underglaze?

Underglaze is essentially a colored liquid clay and can go on both green ware and bisque-ware. They are usually predictable colors for mixing and is acts similarly to paint. Underglaze does not bleed or fuse like glazes do, therefore it is still porous. Underglazes are meant to go under glazes and usually does not react with the glazes on top. - Glazes generally only go on bisque-ware. It is unpredictable when mixed with other glazes. To get a more predictable outcome, it needs to be tested when layered with other glazes. Layered glazes will fuse together, and depending on the thickness and make-up of the glaze, it can run. Because glaze is essentially glass, it is waterproof and can be used for functional-ware unless it isn't food safe - containing hazardous materials (i.e lead, lithium, barium or chrome). And for the sake of your kiln shelves, glazes should not be put on the bottom of ceramic pieces unless they're stilted.

What is Grog?

Grog is a raw material that can be added to clay bodies for increased strength and/or texture. Because grog is material that has already been fired and has been through most of their shrinking, It will reduce the degree of shrinkage that clay goes through during drying and firing. Also, grog creates a more porous clay composition that dries more evenly, so it helps prevent cracking. It is commonly used in clays for hand-building or sculpture, and often in large scale pieces to give added stability. Grog can also come in different mesh sizes. High grog content clays aren't always ideal for wheel-throwing and potters will usually prefer clay with little to no grog, or grog with a smaller mesh size.