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!
Here are some of my favorite colors in leaded enamels. As you will see I mostly use transparent enamels.
A few great colors to get you started.
B30 …these two are true yellows
N27…these three are green yellows
L21 very dark
If there is a B in front of the numbers this means it is from Bovano Enamel Supply Others you can order from E-namels.com and the are Ninomiya Transparent Enamels
But there is nothing more important than making your own test places!
Properties of Opalescent Enamels. Okay, get ready for this. Most modern day opalescent enamels are not truly opalescent but rather semi transparent. A true opalescent is a mixture of two immiscible enamels. (Immiscible Definition
Immiscibility is the property where two substances are not capable of combining to form a homogeneous mixture. The components are said to be “immiscible.” In contrast, fluids that do mix together are called “miscible.”
Components of an immiscible mixture will separate from each other. The less dense fluid will rise to the top; the more dense component will sink. This can also be true of solids but in the case of enamels, it is referring to the molten state.)
The old leaded Thompson were true opalescent enamels. In the case of their 835 Opal White, the glass was immiscible unless fired too hot. If you fire them too hot they become miscible and the resulting glass becomes an opaque. According to the late (great) Woody Carpenter, these enamels also contained arsenic. The “too hot” varied from one batch to another. I have a rather large container of 835 that goes opaque at about 1325 degrees and so as long as you fire under that temperature, your results will be a glorious true opalescent enamel. It should be noted that most medium fusing enamels are meant to be fired hotter than this. It is possible to get them to a glossy stage at 1325 but it will take 3 minutes or more for a small jewelry piece. In actuality, it doesn’t matter how many times you fire a piece as long as it never gets hot enough to change the chemical makeup and cause it to go opaque. Because they are so delicately fussy about temperature, you may find that firing on a layer near the end is safer for you but it really is about the temperature.
The Japanese opals are all semi transparent and not sensitive to overheating. The colors are quite lovely and troublefree but not actually opalescent enamels. Have a look at a Faberge Egg in person some time for an example of Opalescent Enamel. They are delicious.
The Lion and the Lamb
“Let us be dissatisfied until that day when the lion and the lamb shall lie down together and none shall be afraid.” -Martin Luther King, Jr .
The theme for American Jewelry Design Council 2018 is “Together”.
Enamels on Different Metals-What A Difference.
What a difference in the brilliance of the color. You can use foils to your advantage to get the enhanced color you are looking for. Gold foil makes colors have more yellow. Copper will warm colors up. Silver will make the true color and sparkle.
You can add foil anywhere is your jewel. If your base plate is copper add a small amount of silver foil to make a little sparkle with your favorite color of enamel.
A question came up today about hard, medium, and low firing enamels.
Hard firing enamels are fired at a higher temperature as in the 1500’s degree range or longer in the kiln.
Medium firing enamels I think of using in 1400’s degree range, or at higher temp as 1500 degrees, but less time.
Low firing enamels maybe fired in the 1300’s or even in the 1400’s with less time.
The purpose of all this is two things expansion of the metal being used and your technique being used.
Start with copper as it is used most commonly in enamels.
Copper oxidizes the fastest of the metals we use in enameling. We balance this by using medium firing enamels so they melt or fuse before the copper has time to oxide. If it oxides the enamel is likely to flake off or just discolor.
Many enameling on copper use the oxidation to get some beautiful colors.
You can fire at a higher temperature so it fuses quickly not allowing the copper to oxidize. Another way to balance this is to use finer grit of enamel. The finer grit will fuse quicker than a larger grit of enamel without allowing oxygen to get to the copper. This allows the enamellist to achieve that beautiful gold or stunning golden orange copper color.
It is best to know the fusing points of all your enamels so you know which ones to apply as a base or flux. Your base coat of enamel or known as flux, should be the hardest enamel you are applying to your base metal so you do not have these problems.
Above the flux was a lower firing enamel than the top coats. So as the top layers melted the flux rose up and the top layer of enamel sank down.
2) Same here,
The flux coat of enamel was not hard enough to prevent the following layers of enamel from touching the sliver. And the brownish color of enamel is just burnt.
In cloisonné we never want our warm colors to touch the silver. It causes burning. Silver is going to hold heat longer than copper so we use a hard firing base. And in some incidences we will use several layers of the hard firing flux before layering in our warm colors to be very sure the red never touches the silver base.
A comment to address
“I’m torch-firing, I always have my work in my sight so I just watch for signs of melting, which happens very fast. I’ve had “pull through” with Titanium White. Titanium White really reacts nicely with copper and you can get some really lovely, but unpredictable, effects. With a little overfiring the enamel turns a beautiful rust color and in spots will be green.”
Yes these effects can be used to your advantage, this is the oxidation of the copper coming through. And in torch firing I realize you are not going by temperature and have the advantage of seeing all that is happening.
Enameling on copper, as in painting enamel in this piece,
It is necessary to use a hard firing flux as it will be fired many times and I do not want the painting to disappear into the base coat of flux. Also in repeated firings the copper can still oxidize through the enamel and show a color change after many firings. As I paint in my image I need the painting enamel to adhere to the base coat of flux by firing the piece, then I can continue layering my painting with enamel colors (soft firing enamel)that fire at a lower temperature or less time. The domed metal add strength or less expansion. So it can handle a harder firing enamel without so much expansion or movement in the enamel. If the base coat was a lower firing temperature it would become soft enough in firing the image would distort as the enamel base or flux would move before the image enamels fuse. Painting enamels are a soft or low firing enamel= as they are ground to a face powder grit.
A color plate is a very good answer to help you know which is which when you are not sure.
The enamel dot fourth from the left is still grainy after all the rest are fused.
This color plate shows the top row, second from the right, as becoming liquid so much faster than all the other enamels it is completely flat.
If you have three enamel on a plate, one hard firing, one medium firing, one low firing and fire the plate once you will see they melt at different speeds.
If you want to use them all in one project just remember the hard is on the bottom then the medium and then the soft or low firing enamel. This is also why you can use unleaded with leaded enamels as long as you put the unleaded on the bottom as it is a high fire enamel.