More Enamel Vocabulary.
ANNEALING: Softening the molecules of the metal by heating in a kiln or with a
torch to the correct temperature. This enables the metal to be bent and formed.
Temperature for copper; 700-1200F, fine silver; 572F, sterling; 1200F
BASSE-TAILLE: A method of using a textured piece of metal with transparent color
fired over it, showing the texture underneath.
BEZEL: A
thin metal wall that wraps around and is formed over a stone to hold it in
place.
CHAMPLEVE: An enameling technique where there are areas of the base metal are
lowered by engraving, etching, or created by soldering/riveting another piece
of pierced metal on top. The recessed areas are filled with enamel until a flat plane is created over
the surface. The enamel is then stoned down until smooth and refined. Areas of
the base metal may show through.
CLOISONNE: An enameling process that uses thin bezel or cloisonné wire bent
into shapes to form line patterns or compartments. The wires are fused (fired) into
a clear coat of enamel on top of the base metal. Colored enamels are then
applied to the different cells and fired into place, clearing an image or
design. Several layers are needed until the enamels reach the top of the
cloisonné wire. The enamel is then ground flat and may expose the fine lines of
the wire.
COUNTER ENAMEL: The wasted enamel after sifting when you clean up the counter,
which becomes a mix of colors but is still useful. Also refers to the layer of
enamel on the backside of the base metal, critical in evening out the stress
caused by the surface tension of the enamel on one side (coefficient of
expansion).
Enamel:
Ground up glass, in powder form or liquid (powder suspended in distilled
water). May also come in lumps, which can be ground down in a mortar and
pestle.
FIRING SCREEN: The stainless steel screen, which supports the trivet for carrying
the enameling pieces to and from the kiln.
FLUX:
clear enamel with no metal oxides in it for coloring.
GAUGE:
The system of numbers used to tell how thick metal is. The higher the number,
the thinner the gauge is. 18gauge is a good standard for enameling.
HARDNESS: When referring to enamel and the flow of fusion characteristics of
each enamel as is flows across a surface at its melting temperature. ‘Soft’
enamel flows more then ‘hard’.
KILN:
The electric heat source (oven) most often used for enameling.
KLYR FYRE: A brand of water based plant gum binder. A modern version of gum
arabic. Used as the ‘glue’ for adhering enamel to a surface before firing. Can
also be mixed with enamel powder of wet packing and painting applications.
BASE METAL: Copper, fine silver, and high carat gold are the best base surfaces
for enameling. Any alloy containing zinc or tin will cause the enamel to be
brittle and easily break off.
OPAQUE:
Any color that blocks light and does not show the color of the base metal
underneath the enamel.
OVER FIRED: An enamel can be fired too hot or for too long. Over firing is
usually indicated by burned edges and oxidization occurring. A copper base will
start to mix with the enamels and turn things greenish.
OXIDE:
The thin, flakey film that forms on a metal surface when exposed to heat. Rust
on steel is an example of iron oxide. This layer must be cleaned off before
enameling can occur.
PICKLE: Sodium
Hydrogen Sulfate (Sparex) or Sodium Bisulfate (Ph minus). Chemicals used in a
diluted bath of water heated in a crock-pot. This mixture helps to clean off
metal oxides from soldering or enameling.
PLIQUE-A-JOUR: An enameling technique, which uses transparent enamel fired into
small opening or piercings in a metal base. This gives a stained glass or jewel
effect.
PYROMETER: A device for measuring the temperature inside the kiln.
RESIST:
Anything used in the etching process to keep the acid from etching certain
parts of the metal.
SGRAFITTO: An Italian word meaning ‘to scratch’ and in enameling refers to
scratching through a layer to reveal what is underneath
SIFTING:
Shaking powdered enamel through a screen on to a base metal piece.
SUGAR COAT: Under fired enamel which looks a bit like sugar
THERMAL EXPANSION: The rate at which things expand and contract in
response to heating or cooling. Enamels have a thermal expansion rate, which is
similar to copper and fine silver, which makes them compatible for the
enameling process. Which is why the enamel does not crack and fall off the
metal base.
THERMAL SHOCK: A dramatic change in temperature, which causes problems for
enamels, including cracking.
TRANSPARENT: Enamel which has color, but can been seen through to the base metal.
A starting clear coat is often suggested for transparent color in order keep
the base metal from reacting with the color.
TRIVET:
The stainless steel support that holes the work piece for transport in and out
of the kiln. Usually three or four pronged and the edges of the work piece rest
on them, not touching the enamel.
UNDER FIRED: Enamel that has not been completely fired (fused) and looks bumpy
rather then smooth. Sugar coat or orange peel are stages of under firing.
WARPING:
When the metal bows, bends, or twists during thermal expansion.
WET PACKING: Mixing the enamel powder with water, Klyr Fyre, or another binding
agent and applying the enamel like a thick paint.
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