Elmer's Glass Kiln - Manual (Page 7)

The Optional
Glass View Port
Caution: Wear fir-
ing safety glasses
whenever looking
into the optional
view port.
Maximum tempera-
ture for a kiln with view
port is 1700°F/926°C.
Firing hotter will damage the glass. See page 17 for glass port
maintenance instructions.
Loading the Kiln
Place Ware on a Protective Shelf
Always protect the firing chamber by firing your pieces on
a shelf or in a bowl. Do not place the pieces directly on the
bottom of the firing chamber.
Types of shelves and containers:
Fiber Shelf
Place the standard fi-
ber shelf directly onto the
kiln bottom. This shelf is
used to support silver and
gold clay.
Note: Fire only silver
or gold clay on the fi-
ber shelf—never ce-
ramics, enameling or glass. Do not coat the fiber
shelf with glass separator or kiln wash.
Fireclay Shelf
Ceramic fireclay
shelves, available from
Sundance protect the fir-
ing chamber bottom and
provide a smooth surface.
Use a ceramic shelf in
your jewelry kiln to fire ce-
ramics, glass, and enameling.
Insulating Firebrick
Piece
Insulating firebricks
are porous, light-weight,
and can be shaped to sup-
port delicate silver clay
designs. Carve the fire-
brick with a knife or hack-
saw.
Ceramic Bowl
You can purchase an unglazed, small ceramic bisque
bowl from a ceramic supply store. The bowl will last through
many firings. Use it to hold alumina hydrate. You can also
shape hot glass by slumping it into the bowl.
Note: Ceramic shelves and bowls and insulating
firebricks may slow the firing. They absorb more
heat than the ceramic fiber shelf. They also cool
more slowly than the fiber shelf.
Applying Glass Separator or Kiln Wash
Glass and ceramics are fired on a fireclay kiln shelf and
not directly on the kiln bottom. You can also slump glass over
a mold, such as a bowl. The kiln shelf and sagging mold must
be coated with glass separator to keep glass or ceramic glaze
from sticking to them.
A coat of glass separator or
kiln wash will usually last
through several firings. When
the shelf coating begins to
crack or chip, apply a fresh
coat.
When recoating a shelf, re-
move most of the old coating
with grit cloth (available from
sundance). This is an abra-
sive-coated mesh that allows
residue to pass through. Removing the old coating gives you
a smooth surface to start with. Then recoat the shelf using
the following directions. (Both glass separator and kiln wash
will be referred to as “separator.”)
Caution: Do not apply glass separator or kiln wash
to the ceramic fiber firing chamber or to the bottom
of the shelf! Contact with glass separator or kiln
wash can ruin the embedded heating element.
Note: Do not coat the soft ceramic fiber shelf with
separator. If you are firing only silver or gold clay,
you do not need separator. When firing silver clay
with glass, however, fire the piece on a hard fireclay
shelf coated with separator.
1 Mix the separator with water following the directions
on the bag. Stir.
2 Use a haik brush or a soft
paint brush to apply the
separator to the shelf.
(The haik brush is easier
to use because it lays
down a more even coat-
ing.) Each time you dip
your brush into the sepa-
rator mixture, swirl the
brush around the bottom
of the container. This is
because the separator settles quickly. Use two or
three thin coats changing the direction of the brush
stroke 90° with each coat.
3 Dry the shelf before firing. To speed drying, place the
shelf on three ½” posts inside the kiln. Heat at full
rate to 300°F/148°C and hold for five minutes. Then
turn off the kiln and leave the shelf inside.
7
Separator lasts through several
glass firings. Apply new separator
when the old coat begins to flake.