Enameling is the art of fusing powdered glass onto metal to create designs. It is one of the oldest methods used to decorate metals. Enamel powder is applied, by sifting or wet packing to a prepared metal surface and then torch or kiln fired. Metals may be worked - etched, chased, formed, etc. - before any enamel is applied. Enameling is characterized by brilliant, non-fading colors, tremendous durability, variety of color effects depending on angle of light, and versatility - from jewelry such as cloisonné, a type of enameling to bowls and wall pieces. Both copper and silver fired metal clay can also be enameled using the same techniques. Metal should be clean and free from grease for enamel to adhere. Because enamel expands and contracts at a different rate from metal, it is often necessary to counter-enamel the back of the piece to avoid chipping and cracking on the front. This is normally done first. Also, if a piece is not counter-enameled, it tends to bend backwards or warp if the metal is too thin.
There are three types of enamels:
- Opalescent (semi-transparent)
Transparent cold colors look best on silver and warm colors on gold or gold foil. Reds and pinks tend not to work on silver, however; silver foil can be used with a clear base coat to achieve a more desired color. Keep each coat thin, usually three coats depending on your project. Putting on one thick coat can result in clouding and bubbling.
Transparent vs Opaque
Enameled coatings can vary in their color and translucency by the amount of metal oxides contained in the glass, as well as the temperature at which the glassy material was melted and cohered to the surface.
The higher the temperature at which enamels are fused, the more durable and translucent they are. However, if they are fused at a lower temperature they are generally softer, and as such, more fragile and opaque.
Why Wash Enamels?
An overabundance of very fine particles or dust in transparent enamel may cause cloudiness, especially in wet-packing techniques. Washing the enamel will remove these very fine particles. This is accomplished by swirling 80 mesh enamel around in water. Allow the enamel to settle and pour off the particles that are suspended in the water. Another option to remove the "fines" is to screen out the fines from 80 mesh material with a 325 mesh screen (not recommended for lead bearing enamels). The advantage to this method is that the fines can be saved and used for counter enameling.
Sunshine Enamel is a very fine powdered enamel that can be applied like a watercolor. Use individually, or mix colors to increase your color palette. Use a small amount of sunshine enamel in a water color tray and add a few drops of distilled water. A little goes a long way. Mix with a small brush. Add more water is needed. Consistency will be thin. Apply one thin coat at a time. If a more intense color is desired, apply a light dusting of flux to cover the dry, unfired sunshine enamel and fire. Repeat this process until the correct depth of color is achieved. Adding one thick coat may result in bubbling. Always apply a dry flux coat for all firing applications. Unused Sunshine Enamel can be stored after your project. Just add water and mix when you're ready to start next project.
Note: This product cannot be applied directly to metal. Always apply this product to a piece that has been previously enameled. After application, let dry and then sift a light, dry coat of Thompson flux or Ferro coating flux, coating piece completely. This will help preserve the color integrity of Sunshine Enamels.
Separation Enamel is technically not enamel/powdered glass. It is used with squeegee oil and painted on top of enamel in various patterns. When applied, it disrupts the surface tension of the enamel that surrounds it which give a marbleized look. It can be used on fired copper clay or copper sheet. Separation enamel works best with opaque enamels.
Metals Suitable for Enameling
Every combination of metal and enamel will have their own unique properties, some good, some not so good. Most metals in general can be coated with enamel. This does not mean an enamel selected at random can be used successfully on a randomly selected metal. The enamel, technique of application, and firing conditions must be carefully selected the metal chosen. The most commonly used metals are pure copper, gilding metal (95% copper, 5% zinc), sterling silver, fine silver, karat gold (18 karat or higher) and low carbon steel. Sterling silver can be enameled but must first be depletion gilded. Depletion gilding is the process of heating sterling silver sufficiently to oxidize the copper in the surface layer of the alloy and then removing that oxidized copper layer by soaking in a mild acid solution (pickle). This process leaves a thin layer of fine silver on the surface of the metal.
It is always a good idea to create a test strip with the colors for your project to see the finished fired color. If you are interested in more details regarding metal types and enameling, The
Thompson Enamel Workbook includes in depth information on this topic.
Use your enamels in a well ventilated work area. Wear a protective dust mask when cleaning and sifting enamel powders.
Basse-taille (pronounced bahss-tah-ee) is an enameling technique in which the artist creates a low-relief pattern in metal, usually silver or gold, by engraving or chasing.
Pronounced (prounced shahn-luh-vey) was invented during the medieval period. The word champlevé means literally 'raised fields' and refers to the way that beds were dug out of a copper plate to receive the powdered enamel. This method is still used today in jewelry making.
Cloisonné (pronounced cloy-zon-ay, French for ”partition”) is an ancient metalwork technique that makes use of small, precious metal filaments and colorful glass enamels to create brilliant artwork. The metal wires are bent into shapes to create small cells, (partitions) of designs, and many coats of finely ground glass enamel are fired into them until one unique piece of art is rendered. Cloisonné is commonly used in jewelry making.
Plique-à-jour (French for "letting in daylight") is an enameling technique where the enamel is applied in cells, similar to cloisonné, but with no backing in the final product, so light can shine through the transparent or translucent enamel. The effect is similar to the look of stained-glass and is considered very challenging technically. The technique is similar to that of cloisonné, but using a temporary backing, such as mica.