DO NOT MIX STAINLESS
STEEL AND CLAY MOLDS IN A FIRING. DO NOT mix different types
of CLAY molds in a firing, always make sure that all your
molds are of the same manufacture in a firing.
MAKE SURE YOUR MOLDS AND/OR SHELVES ARE KILN WASHED AND DRY
EACH TIME YOU USE THEM!
When using molds ULP and ULR (large uplighters)
and satellite dish, for the slump firing - use a program with
a slightly lower top temperature - e.g. 785oC (1440oF) Using
a hotter firing (800oC - 1470oF) will cause glass to avalanche¡¯
down the mold, also use when doing ¡°appliqu¨¦¡± enamel decoration
in these molds.
Molds ONLY need to have the kiln wash layer
removed when it is too thick to give a good impression to
the glass. It will chip and flake when too thick, and also
start to ¡°fog¡± the glass when the layers are too thick. SOAK
the mold in water, and then remove the layer CAREFULLY with
an old credit card or similar plastic scraper, (not metal)
until back to a clean clay surface. MAKE SURE you DRY the
mold before using it, or the steam generated in the clay could
burst the mold.
ULP, ULR, UFO1, UFO2, PLXL, XLFB, are all
better with 6 mm (1/4¡±) or thicker glass.
Kilns which are deep enough to have more
than one layer of molds should be stacked carefully to avoid
extra heat build up. The stacking of the shelves should allow
for a space equal to the height of the mold before the next
shelf is placed. Care should also be taken not to have the
shelf props touching the mold skirt, which could cause ¡°hot
Molds should be stored flat, and if stacked,
should have like sizes together, face-to-face only. Do not
put smaller molds inside large ones, this could chip and damage
both molds! The original packing box is also an ideal storege
Do not carry molds by only one side of the
skirt, use both hands to support the entire weight of the
mold. This is why the ¡®hand-holds¡¯ are cut into the skirt!
This also applies particularly to the large diameter molds.
When washing off old layers of kiln wash,
take great care not to lean too hard on the skirt of the mold
while scraping the surface, this could cause minute cracks
to form from the undue pressure, and the mold could then crack
in the next firing. Remember that the weakest point is where
the handholds are cut out, the skirt is narrower because of
When loading a kiln, take care not to push
the molds against each other with undue force, or bump them
against anything hard, as this could chip or crack them.
Regardless of the fact that all this sounds
as if the molds are fragile, with the proper care and attention,
they will give you a long and reliable service!
Due to the nature of the materials used for
making the molds and the method of forming, a small difference
in finished size can be expected from time to time.
Please check the size of molds before cutting glass. Glass
should not be cut larger than the mold.