ClayWorker's Newsletter Volume #1 Issue #2

Inspiration Through Clay

It is often said that clay is the only medium where creativity can be surpassed beyond any other art form. Yet, what makes clay such a satisfying material to work with? And where does the clay take us to give us our creative ability?

To answer the first question, we must go back to our childhood days when our backyard was our playground and getting dirty meant having to take an extra bath before bedtime. Probably the memory that sticks in many potters' minds is the stories their parents tell of mud pies and eating dirt. For those who never experienced such a childhood past time, we envy you. Or do we? There was something about being close to the earth as a child, working with water and mud and all the utensils, creating inedible (but sometimes tasty) pies and cakes.

In this issue:

• Editor's Corner

• Inspiration Through Clay

• Don't Under Estimate the Power of Colorants

• Pottery Tips

• MicroKilns - Ceramic Kilns or Bad Idea?

• Free Class!

• Advertisements

Editor's Corner

With our first issue behind us, we now nestle down to tackle the rest of the year. Our studio is busy preparing for the upcoming year with new events at the retreat. We have a lot of projects planned as we begin a new season.

We are preparing a new resident ceramics program designed specifically for the ceramic student who desires a unique one-on-one training atmosphere. The program will offer educational classes, workshops and studio training. Students will have the opportunity to complete a detailed portfolio of their work while residing at our facility.

What gives this program its uniqueness is two areas of education not offered in any undergraduate or graduate college. A complete glaze chemistry program that teaches students to design, develop and put to test glaze chemicals, while problem solving issues that arise from developing glaze recipes. And an in-depth program in pottery history, from the Jomon period to present day. We believe this new program addition will benefit all who choose a complete pottery educational experience in a relaxed learning environment. This ClayWorkers issue continues with the glaze formulation series; Don't Underestimate the Power of Colorants, which should prove to be an article packed with information for every novice and advance potter.

Enjoy this issue of Clay Workers Digest!

Editor in Chief, Ti Phillips

MicroKilns - Ceramic Kilns or Bad Idea?

In our high-tech world, designers are rushing to create new and innovative ways to quicken the pottery design process. And although potters are in complete agreement that technology has its place in the studio, the microkiln is one of those innovations that has been met with mixed reviews.

Originally developed overseas, the microkiln is now manufactured in the United States under various brand names. Typically the same design, the microkiln comes in two sizes, small and medium. We purchased the medium microkiln which included fiber paper to protect the surface of the kiln. Hoping it would be large enough to fire a small bowl, we soon found that it was only 3.50" high and 6.50" wide, with a firing chamber of only 1.77" high and 4.33" wide.

Our test would include a porcelain tile with the application of china paint. We followed the instructions by placing the fiber paper on the surface of the microkiln base then placed our 2" x 2" glazed porcelain tile on the fiber paper. Placing the lid on the base, the microkiln was placed inside the microwave and turned on to the recommended time, 10 minutes. When the microwave turned off, kiln gloves were used to place the microkiln onto a brick surface to cool. After waiting the recommended 20 minutes to cool, we removed the lid to the microkiln and examined our tile. The glaze did indeed melt and fuse to the porcelain tile.

We then chose to repeat the process using our own low temperature china paint glaze on the test tile. The glaze was applied with three coats of one color and a painted glaze decoration on top of the base color. Again, we fired the microkiln to the specifications. Upon removing the tile, we found that the glaze melted but did not completely fuse to the porcelain tile. The glaze fused to sections of the tile, but chipped when tapped lightly with a metal spoon. Once again, we repeated the porcelain test with our china paint glaze and increased the timer to 11 minutes. This test proved successful.

Upon testing we found that microkiln does what it claims in firing low fire glazes onto a ceramic body. However, the microkiln lacks any way to make visual determinations on the progress of a glaze body. Therefore, several tests may be required to determine the actual time needed to fuse the glaze to the clay body. This will result in much wasted energy use and materials.

Also, because of the small size, it is extremely limited in the firing size of the ceramic object. There is no real use for the microkiln in the potters' studio, even as a test kiln because of the firing limitations and size. The cost of the microkiln is about half that of the cost of a good used test kiln, if the potter is in need of one for testing glazed tiles.

The microkiln does not allow for bisque firing, and we feel that fluctuation in the microwaves ability to heat after extended periods of time may cause further failures of the microkiln to melt and fuse glaze. The total cost for the microkiln, fiber paper, china paint pens and 1100 watt microwave was under $300.00. Therefore, it is our recommendation that the potter should save their money and purchase a used or new test kiln rather than the microkiln for glaze testing.

Don't Under Estimate the Power of Colorants

Series #2 On Glaze Formulation

In our last series, we covered the use of a base glaze and a few raw colorants to create primary colors at cone 05 temperatures. Although many potters, who have had basic experience in glaze mixing, can come to the conclusion that primary colors can be achieved at low and medium temperatures. But when attempting to create high temperature primaries, the steps to create a recipe become more involved.

Glaze colors are based on three specific criteria. First is the firing temperature, second, the raw materials included in the base glaze and third, the opacifiers and colorants used. The higher the temperature, the less stable the colorant remains. Add the fact that many different materials are in a base glaze and create various chemical reactions, a colorant known to produce a specific color may surprise the potter when reaching high temperatures.

Therefore, a different strategy is taken to stabilize a colorant so that the base materials and firing temperature will have less reaction to the purity of the colorant. Frit, a unique form of stabilization, is used to reduce the negative effects on a colorant while also creating a safer colorant to introduce to the glaze mix.