DRAFT: This module has unpublished changes.

 

 

 

Enamel, basically is glass that is fused onto metal at very high temperatures.
When beginning any enamel project it is important to make sure that the initial molecular bond is secure. This will prevent problems later on.


First the metal needs to be prepared to receive the enamel. The generally takes four basic steps


1. Anneal: heat to 1500 degrees – about 1 minute in the kiln for a 2” circle slightly shorter for smaller pieces (45 seconds) and longer for larger pieces (up to 2 minutes for a 3” square. This process burns off impurities like oil and tooling residues, but adds another: fire scale, which is the reaction of a base metal like copper to oxygen (oxidation) The piece should be glowing red and covered with grey fire-scale

2. Quench: drop the red-hot piece in cold water. This will remove most of the fire scale.  Never drop a piece with enamel on it into water! Quenching is only done to the plain metal

AT THIS POINT THE PIECE SHOULD ONLY BE HANDLED BY THE EDGES - THE SURFACE TO BE ENAMELED SHOULD NOT BE TOUCHED.

3. Pickle: immerse the piece in a mild acid (usually Sparex #2). This will remove the remaining fire scale in just a few minutes. (Note: jewellers often heat their acid to make it work faster – this is not recommended with enamelling, as the enamel itself is often acid sensitive and harmed by this practice)

4. Neutralize: The pickle leaves an acid residue that can be removed with a little baking soda on a toothbrush (or in a pinch, spit) The piece should then be rinsed and dried with a paper towel (water can leave mineral residues) being careful to touch only the edges with your fingers.

Your copper is now ready for enamelling.

 

Some enamelists are not this meticulous in preparing their metal - but I find that the more careful you are in the initial steps - the less likely you are to have problems later.

 

 

Enamel can be applied by sifting it through a sifter of appropriate size. A thin coat of gum binder (Klyr Fire) is generally used to make sure the enamel does not get knocked off accidentally. This is applied directly to the surface of the copper immediately before sifting. An even coat should be sifted over the piece,  and on to a CLEAN piece of paper. The excess enamel can be returned to the jar using the paper.
The piece should then be placed on a trivet or firing rack to dry before going in the kiln. It must be completely dry before firing.

 

Pieces go through various stages in the kiln - it is essential to familiarize yourself with these changes.

      a) fusion beginning        b) sugar fire           c) orange peel         d) almost mature        e) mature

 

Most colours are fired for approximately 1 minute at around 1450° F , but few colours should be taken to maturity in the first firing. Generally Opaques should only be fired to orange peel stage until the final firing, and transparents should be fired to maturity (transparency) in the first layer, and sugar fire in subsequent firings.

 

A piece must reach AT LEAST orange peel to achieve fusion of the glass and metal.

 

Once the piece is cool, remember to only touch it on the edges. It should be placed metal side up in the pickle to prepare for enamelling on the other side. Steps 3 and 4 should be repeated before enamelling.

 

DO NOT QUENCH A PIECE WITH ENAMEL ON IT. ONLY QUENCH BARE METAL.

                              

DRAFT: This module has unpublished changes.