Foil for Enamelist
By Coral Shaffer
Foil for enamelist is something we all need to examine to be able to use them successfully in our jewels, and Coral has written a great article here for us!
Enameling foils, heavier than leaf but thinner than aluminum foil, are often used for special effects in enameling. Gold and silver foil are the most commonly used. Often they are used to add more brilliance to the transparent enamel overcoat or to prevent unfavorable metal/enamel reactions but can also be used for other design purposes.
Piercing: Many enamelists pierce the foil for enamelist with small pin holes in order to avoid blisters forming under the foil when it’s fired. Others don’t believe this is necessary with the thinner foils. I think the thicker Ginbari foil from Japan should be pierced. The easiest way to do this is to lay it on a sheet of 220 sandpaper, cover it with a piece of felt and roll a brayer or a rolling pin over it once or twice. Or fold the sandpaper in half, put the foil in between and tap with a rubber mallet. When you peel off the foil, hold it up to a light and you will be able to see light shining through the tiny holes. Gold foil is porous by nature and does not need to be pierced.
Annealing: Annealing heavy silver foil for enamelist makes it easier to work with especially if you need it to conform to a curved surface. Place it on a clean piece of mica or lava cloth. If you need to anneal more than one piece of foil at a time, sandwich them between pieces of mica or lava cloth. If the pieces of foil touch they might melt together when fired. Anneal at 600°F. to 1400°F. for a few minutes. You know that it is annealed if it drapes easily and doesn’t make a harsh rustling sound when you shake it.
Manipulation: There are many ways to use the foil enamelist. Often enamelists cut the foil to fit a cell in cloisonné but you can also cut it into more elaborate shapes and/or punch shapes out of it using paper punches. It is important to know that anytime you are manipulating foil you need to keep it between pieces of paper. Tracing paper works well because it is thin and you can see through it to see where the foil is placed. However thicker paper such as copy paper is better for punching. You can cut multiples of a shape at one time by layering the paper and foil. If you have difficulty keeping the layers from sliding, use paper clips, mini clips or staples in strategic locations outside of the design area to keep the layers in place. You can also decorate foil by painting or silk screening designs on it with overglaze painting enamels. The heavier Ginbari foil can even be embossed. You can use found materials like lace or leaf skeletons for the embossing plate as long as the depth of the object is no more than 1.5/64th of an inch. Or you can make your own embossing plate by bending 24 ga. round wire in the desired pattern and gluing it to a flat, non-porous platform. Or make the embossing plate by drawing a design on tooling foil, indenting the design lines and filing them with epoxy. Lay the ginbari foil over the raised line side of the embossing form, cover it with a piece of felt and roll over it with a rolling pin or brayer. Attach this to a fired enamel and fire until the enamel gets molten enough to rise up and fill the raised areas.
I save all my ginbari foil scraps to make foil “bits”. Put the ginbari foil in a blender with some water, turn the blender on high for a few seconds, pour the mixture out into a sieve, dry out the foil bits and separate them by size by shaking them through a series of shakers – like salt and pepper shakers. You can then shake them onto an enameled piece freehand or control the design outline by using a stencil. You can also wad up leftover bits of foil and melt them into balls with a torch.
Adhering: However you intend to use your foil you need to attach it to your enameled piece. Possible “adhesives” include Klyr-fire, an enameling oil, certain gold leaf sizes*, hairspray petroleum jelly, alcohol and plain water. Water has not worked for me – tiny pieces of foil tend to “take off” in the kiln and fly about. Klyr-fire or CMC can be used on a vertical surface (and with the foil “bits” described above) but I prefer to use a liquid that does not contain water such as a size or hairspray. For small cut outs I use petroleum jelly. Paint the enamel surface with a thin coat of your choice of “foil holding agent”, lift the foil on to your piece with a damp brush or damp cotton swab. If the holding agent dries out and you need to adjust the position of the foil, use a brush to slip a dab of it under a corner of the foil and coax the foil into place with the brush. After drying you can smooth the foil by covering the foil with a piece of wax paper and rolling your finger over the piece.
Firing: Fire at the temperature needed by the enamels underneath, usually 1400°F. – 1500°F. for 2 to 3 minutes. The lower temperature will result in more “crinkly” foil and the higher temperature in smoother looking foil. 23K gold foil and leaf turn darker when fired but this can be remedied by covering them with a transparent enamel and refiring. Enameling over silver and 23K foil will keep them from tarnishing.
Gold & Silver Leaf: Both gold leaf and silver leaf are very thin and difficult to manipulate. Patent Leaf is lightly attached to a paper sheet and is easier to use providing you use a sticky enough adhesive on your piece to dislodge the leaf from its backing. Leaf is best used in a whole sheet or cut into simple shapes between sheets of paper. Don’t try to touch it with your hands or it will stick to you! One way to attach leaf to a pre-enameled base is to paint the base with the appropriate adhesive and to lay the piece onto the leaf (rather than vice versa). If you need to handle the leaf, dust your fingers with baby powder first or use bamboo tweezers. Gold leaf will often pull apart when fired producing an interesting crackle effect. The silver leaf sometimes will almost disappear upon firing leaving a ghost like pattern. Overlap silver leaf if you would like a stronger effect. Palladium leaf can turn pretty shades of turquoise and purple when fired but it should not be covered with enamel or it will loose its patina. Leaf is so thin it does not need annealing or piercing.
Thank to Coral for this awesome information!