Watercolor underglazes work best on bisque fired pieces since a great deal of water is needed to apply them.
Useful ceramic glaze test tiles.
In this post i ll share lots of different examples of ways you can make your own test tiles.
Here are examples of the test tiles i use regularly.
Once your ceramics have gone through their glaze firing they ll be vitrified and the process will be irreversible.
Every potter wants to be certain that the products they are selling are safe and will stand up to the rigors of use in the kitchen.
Captions on the images describe each step in the making process.
This provides a more direct transfer of information effort from the testing to.
Making a test tile.
The hole in the base allows the tile to be hung on a glaze bucket or on a display.
Test tile in 30 degree position.
And to improve your results it helps to have test tiles that mimic the kind of work you make.
The word test tile can refer to any shape of clay that s used to test glazes slips underglazes engobes etc.
In this video an excerpt from his dvd understanding glazes.
But because there are so many variables involved in ceramic glazes clay body and glaze fit variability in chemical content temperature variability in kilns organic materials etc it can be challenging to know whether the food safe ceramic glaze recipe you.
On the test tile above you can see the difference one coat of clear glaze makes to the watercolor surface.
Otherwise if you re like me you forget very quickly.
Marigold pear and aqua on 480m stoneware clay without grog.
Some helpful hints make your test tiles using the same process you use to make your work with.
How to test tweak and perfect your glazes john britt shows several different ways to make test tiles.
Test tiles can be any shape you wish and can be made in a variety of ways.
The importance of test glazes.
Most people use some form of.
Test tile in upright 60 degree position.
Using this type of underglaze can achieve painterly effects.
I stamp the back of the tile with a code for the type of clay and there is ample space to write information about the test using an underglaze pencil.
It allows you to test combinations of glazes easily and inexpensively and serves as a permanent reminder of what a glaze looked like on a certain clay.
All the test tiles made in the glaze gallery are made in the fashion pictured below.
Given all the different ways different clays can react with different glazes it s important to know what you re getting.
C 20 cobalt over sm 11 white at cone 6.
Celadons on speckled stoneware.
Chances are you ll find one that makes sense with what you are making.