FIRE AWAY ON GLAZE EXPERIMENTATION

In the last issue you were given instructions for testing two
materials ina line blend.

From those tests which are not satisfactory with just two materials
make an educated quess for a third material which may he blended
into a tri-axial sequence. You may already have all the line
blends tested; if so, place them on the table in the form of a
triangle. Use the diagram on page 9 to determine the quantity of
each of the ingredients needed to make the tests for the inner

part of the tri-axial.

When you have done several tri-axials, compare them for similari-
ties and then look for other possible combinations. Always keep
looking fot the relationships which occur between tests using a
common ingredient. You become more familiar with the individual
materials as a result of this awareness.

As with the line blend, all the tests in the tri-axial will not be
perfect glazes. Because, to date in this experimentation, all
tests have graduated at the rate of 20 parts per step, you may
want to run some inbetweens using steps of five orten Maybe an
adjustment of 5 or 10 on one direction or another might be
sufficient to cause a melt, or stiffen an over-active ingredient.

If that doesn't produce results, study some more and consider
using a fourth material. At this point you would go to the
quadraxial. (See diagram on page 10).

This system of testing was used by Robin Hopper in his article
on “Low-fire Leadless Glazes” in the October 1970 issue of
"Western Potter".

In the quadraxial diagrammed for this sequence, the line blends
or outer lines of the square have been kept in the same ratio as
the first line blends and the tri-axial borders so that they may

be interchanged in your experiments. Use the line blends already
tested and then follow the diagram to obtain the quantities of
materials for the inner portion of the quadraxial.