Glaze Application: Applying Crystalline Glazes |
This is a fountain glazer. It consists of
a large basin that holds glaze, and a simple pump called a bell pump that is operated
by a foot pedal. The basin is filled with glaze, some of which flows down the
center pipe into the bell reservoir. When the artist steps on the pedal, it causes
a jet of glaze to flow up through the basin. In the second picture, I am carefully
controlling the speed with which I am pressing the pedal . If I pressed hard and
fast enough, I could cause the fountain of glaze to go all the way to the ceiling.
Glazing a boat-shaped form. Note the cascade
of flowing glaze. The entire inside of the piece is uniformly coated.
The fountain glazer easily covers small and
medium sized flat forms. There is no need to wax the backs.
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| Glazing a bowl. First,
the bowl is dipped down to the foot-ring line. Then the bowl is lifted from the
basin and the inside of the bowl is fountain-glazed.
There are limits to
how deep a bowl can be dipped. But the insides of very
big bowls, even as large as the basin, can be fountain-glazed. The jet of glaze
fans out when it hits the bowl, easily and uniformly covering the entire interiors
of bowls. |
There is a limit to how far the glaze will
fan out when it hits a flat, horizontal surface. It may be necessary to operate
the pump multiple times to cover larger plates and platters. In the second photo,
I am re-fountain glazing the corner of a flat plate.
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| I use a plastic threaded
pipe to guide the fountain of glaze into forms that have narrow openings such
as vases.
Note in the first photo that several small holes have been drilled
into the base of the pipe to allow glaze to flow back down into the bell pump. |
All of the above six pieces in the above demonstaration
photos were glazed in rapid succession in very little time.
The
fountain glazer is indispensable to me. I "raw glaze" or "single-fire,"
that is, I apply my glazes to unfired, un-bisqued raw clay or greenware. Most
artists use glaze tongs and dunk their bisqued work in large glaze buckets.
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The grabbing action of glaze tongs such as those pictured
above will destroy raw greenware, especially once the clay starts to absorb moisture
from the glaze. Additionally, the fountain glazer coats my work in a very uniform,
predictable and manner, which is crucial for preventing and controlling the running-off
of glaze during firing that crystalline glazes are so notorious for. |
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| Glazing the Outside of a Vase:
In the first picture I am drawing a line 1/4" up from the bottom of the
vase by holding a pencil against the base while rotating the piece on a lazy susan
bearing.
Picture 2: ready to dip.
3: dipping to the pencil line.
4:
excess glaze dripping back into the bucket.
click on images to enlarge. |
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The RAM bell pump.
The
top and bottom castings are identical. Sandwiched between the two halves is a
rubber membrane. When you step on the foot-lever, it pushes a rod that enters
the lower casting-half upward. The rod terminates in a small plate witch presses
against the rubber membrane. The membrane travels upward, forcing glaze out of
the upper bell-half through the central threaded pipe. |
