Enameling and Firing Information Information
1. Transparent Enamel numbers and names that do well directly on clean copper. If not on this list, test fire a sample. All Opaque's work well directly on copper.

2110 Wax Yellow
2115 Mars
2170 Van Dyke
2220 Chartreuse
2325 Gem
2420 Sea
2660 Nitric Blue

2520 Aqua
2530 Water
2615 Periwinkle
2625 Winter
2650 Heron
2680 Prussian
2755 Concord
2.Firing time and temperature for most enamels transparent and opaque is 1450 to 1500 degrees F for 2 min . Larger pieces may require a bit more time so watch for gloss. Underglazes, Overglazes, and Decals may require lower temperature of 1250F. Decals must be water slide, enameling decals. (See resource below)
3.Exercises / Demos I will cover in class (May not be in this order) I have added links to the list that will take you to videos from vendors, artist.or youtube.com that you may want to see as future reference. General Enameling Process, Silkscreen, Stenciling, Rubber stamping, Painting, Underglazing, Overglazing, Sawing, Texturing, and BasseTaille and Sgraffito. For those interested I could do a torch fire piece.
4. ARMOUR ETCH creates a matt finish on enamels for you to paint or pencil a design with underglaze pencil or paint. It is very similar to bisque fired ceramics when finished. I leave the acid on for 10 minutes to get a nice matt finish, then wash off the acid with water. This etching medium is not as strong as Ferric Chloride because the concentration is very low.. This process is done outside. Don't wash this acid down the studio sink. There should be a hose outside. Pure Ferric Cloride is for etching deep cavities in the copper. Usually on thicker gauge copper like 18 or 20 gauge.
Copper is etched in a bath of Ferric Chloride. Creating attractive etched metal pieces requires masking portions of the metal to prevent the etchant from etching those areas. Any areas you don't want etched needs to be mask with a resist and duct tape should be used on the back not to be etched. A piece of styrofoam can be used to float the piece in the bath face down. The unetched areas will be the high points on the metal.
Sharpie pens or Paint Pencils work well for a acid mask medium. Does not have to be black.
Lines should be a little wider than how you’d like them to be when the etching is done to allow for the fact that the etchant will typically undercut your design lines a bit. If you’re doing a deep etch, use lines that are at least 1/32" wide and metal 20 gauge or thicker. Finer details might be lost. I have etched 26 gauge but it must be a shallow etch which is achieved by less time in the acid bath. If you’re doing a deep etch, use lines that are at least 1/32" wide and metal 20 or 18 gauge or thicker. Remember that the larger the number gauge the thinner the metal. I have etched 26 gauge but it must be a shallow etch which is achieved by less time in the acid bath. This is good for BasseTaille designs.
5.Underglazes have no glass in them. P3 is an ink type underglaze then when fired on enameled surfaces like 1030 opaque flux will attach to the base enamel, then by creating a type of sandwich with a flux like 2015 over the P3. P1 is an overglaze and has glass in it. Underglaze doesn't melt so it stays put where you put it and does not flow. Overglazes will flow so firing should be lowered to around 1250 F to keep it put where you want it. Underglaze can be painted on with brush or use a underglaze pencil or quill or speedball pen to apply. Underglazes, Overglazes and Decals is fired at 1250F but watching for shine determines time. TESTing a piece is always recommended before firing these materials.
6.Steps to Enameling on Copper
---1.What is Enameling - Ground glass formulated to fuse to metals. What makes up the type of enameling we will use. The process starts with a glass compound typically consisting of quartz sand ground to a powder, iron oxide, potassium oxide, and borax, which together are colorless. Color in enamel is obtained by the addition of various minerals, often metal oxides cobalt, praseodymium, iron, or neodymium. The latter creates delicate shades ranging from pure violet through wine-red and warm gray. Enamel can be transparent, opaque or opalescent (translucent) depending on the type of base silica used.
---2.Preparing the metal is an important part. It must be cleaned of any dirt or grease from finger prints. After cleaning handle the metal by the edges. Use a cleaning agent like penny bright and a scrubbing pad. When water sheens in a sheet the metal is clean. Clean both sides so it can be counter enameled.
---3.Basic Firing is done for most opaque and transparent enamels at 1450 to 1500 degrees F. Coat the back surface with counter enamel to be fired to relieving any stress put on the metal after face coat is done. It will help keep it flat. A good fired piece has a flat gloss finish not a sugar coated or orange peel look which means it is underover fired. Some larger pieces my require more fire time.
7. Torch Firing Enamels-Here is a video on Torch Firing Torch Firing at Cooltools.us Only small pieces should be torch fired.
8..Pencil Underglaze-Amaco developed an underglaze pencil at $15 but a 2B 4B graphite lead will work if you have good tooth from the Armoral Etch. You can shadow with a paper blender (stomp)..Here is a great video link on this process at which is about 50 minutes but is very informative. Using Pencil Underglaze. Here is CoolTools video version of the same process but the first video is the beast one. Enameling with Pencil Underglaze
9..P3 Underglaze - Fine Line Black from Cooltools This underglase is put on with a speedball tip or a quill pen for finer lines.
10.Watercolor Underglaze- Considered a ceramic underglaze has no glass but can be used on enamel with a clear top coat over it'd Sunshine overglaze does have glass and therefore needs no clear top enamel. Ceramic potters use under and over glazes on bisque fired pieces but they are used on enamels is pretty much the same with much less firing time. (FYI Cone to temp chart below))
11..P1 overglaze - Mix powder with clove, pine, or lavender oil and draw with a quill pen. Fired with no clear flux cover enamel
12.Using Sunshine Overglaze Paints - Sunshine Paints at Cooltools
13.Excellent 55 minute video on processes we have covered like underglaze pencil, painting, and clear finishing Underglaze Project Development
This chart is for directions using ceramic cone temperature and you need the degree equivalent.











































Enameling Resources  

Thompson Enamels
Help and Information about Enamels
Liquid Form Enamels Down loadable PDF files.

Thompson is the main source of colors and tools. Shipping is calculated after order. Price of enameling varies by color and size i.e. 8oz 1030 is $31 in May 2023. Shipping showed at $17 came but was actually $9.
Cool Tools Good source for many types of creative work. Get underglaze paints both sunshine brand and underglaze watercolors.
Milstone Decals, Delphi Decals, Sanbao Decals Most companies ship 10 sheets for around $14. and the same for 1 sheet. Sheets run fro $6 to $9 ea.
CoolTool decal firing instructions . Milstone firing instructions.
Simple Decal firing with temperature and time or until glossy.
Shot for 2 min at 1250 degrees., if not glossy yet, back in kiln for about 1 min.
AAE Glass

Smaller Decals good for Jewelry : Firing instruction and information for AAE glass and enamels

Liz Worthy decal Information Great info if you were going to invest in printing decals.
Surfactant- (Suface Active Agent) How does surfactant affect surface tension?
When a surfactant is introduced to a liquid like water, some of the surfactant molecules migrate to the surface of the water. This creates a layer of weakly attracted molecules on the surface of this water/surfactant compound. The surface tension of this liquid is lower than if it were just water.
CoolTool.us Using Decals - Cool Tools Decal Video
Martha Banyas using underglazes 12 min. slide show with voice showing types of underglaze work.
Sunshine Enamel Paints Demo Sunshine Overglazes fired 1300 for about 11/2 minutes depending on size or until glossy.
RioGrande Good source for metal, metal clay, and tools which can be pricey.
SES Enameling Site The Information Section is full of my resource links.
Scientific analysis of bonding glass to metal For those interested this discusses the oxidation of various metals which forms the bond between metal and glass.
My Jewelry Ideas and others that I admire. Mary Hettmanperbeger / Becky Burt (More stone and silver but great design.) /
Acid Etching Metal Ferric Chloride is a pretty strong acid so safety is important. Glove and Goggles Recommended. Design etching creates cavities for enameling or patina fills. Armour etch or Etch All is used to create matt finishes on enamel. (See Chart Below)
Micro Fasteners For cold connections for those who are not set up to solder.
John C. Campbell Folk School Great School in Brasstown NC for all kinds of crafts.
FDJTools Everything you need for Jewelry, Beading, or Metalwork.
Copper Foil Copper Foil on Amazon is best price at this link.
Acid etching Etching uses Ferric Chloride which requires some safety precautions.
E-namel Sell Japanese, Vintage, Opalescent, Milton Bridge Enamel, Base in England, shipping is a factor
Working with Mica Powder video Mica is a heat resistant silicate minerals that can be split into thin layers. I can be used as a firing surface in kiln at high temperatures. As a powder it gives a sparkle to paints and enamels.
Sunshine Paints on glass Video for on glass only.
Video for making Die Forms @ CoolTools.us
Check back as I am adding resources periodically


























I have choosen this Technical Enameling information from various sourses that I think is pertinent for this class.

I will demo and discuss most of this information in class and I demonstrate the various enameling processes.

What is Enamels

Here are some of the enameling techniques used and taught in classes at John C. Campbell Folk School in Brasstown North Carolina.


What is mesh size?
80 mesh enamel is the standard particle size available to our customers unless specified otherwise. 80 mesh is glass ground to a particle size which is slightly finer than granular sugar. It is normally applied by sifting, but can also be mixed with water and inlayed or charged onto to the substrate surface.

80 mesh means there are 80 openings in a standard wire mesh screen per linear inch. 40 mesh means there are 40 openings in a standard wire mesh screen per linear inch. We suggest using a 40 mesh screen in our sifters to apply base coats of 80 mesh enamel to metal or glass substrates.

6/20 mesh enamels are particles that have an average diameter of about 1/16” to 1/8”. These particles are ideal for bead making. Lump enamels (unground, unscreened enamels sometimes referred to as ‘frit’) are particles that range from 1/16” to 1” diameter chips or lumps. A variety of painting and liquid enamels are also available for specific substrates.

What should I know about how to safely use Thompson Enamel products?
All of Thompson’s enamel products are glass of one form or another. Care should be taken not to ingest them. These products, however, can be used quite safely if you adhere to the following housekeeping and hygiene rules:

Rule 1. Keep products out of reach of children and pets.
Rule 2. Keep your work area neat and clean. Keep your clothing clean.
Rule 3. Use your enamels in a well ventilated work area. Wear a protective dust mask if you are working with fine enamel powders for an extended period of time, especially when sifting enamels.
Rule 4. Wash your hands prior to eating. Do not smoke or handle food when you are working with enamels.
Rule 5 Assume everything by the Kiln is HOT

Please call 859-291-3800 if more specific information on any particular product is required.

What is enamel?
In general terms, vitreous enamel, porcelain enamel, copper enamel and jewelry enamel all refer to the same thing. Enamel is a glassy compound applied to and bonded by heat (fusion) to a metal surface; to a copper surface at 1450 degrees F., and to a glass surface at 1100 degrees F. to 1500 degrees F.

The most common glass is a fusion of silica, soda, lime, and a small amount of borax. Though normally transparent, various amounts of opacity can be produced by adding or growing crystals within the glass structure. A wide range of colors are produced by incorporating certain elements, mostly transition metals.

The physical properties of glass can be controlled to permit bonding to most metals, for example, gold, platinum, silver, copper, steel, cast iron and titanium.

The word ‘Enamel’ refers to the glass material as well as to the finished product.

How is it done?
Enamel (glass) is crushed to a powder somewhat finer than granulated sugar and somewhat coarser than flour. This powder is applied, by one of several methods, to the metal or glass surface. Next the article is heated to 1100 to 1500 degrees F., either in a pre-heated furnace, a hand held torch, or for enamels fused to glass, in a kiln. For metal, in a preheated furnace the article may be fired from 1 to 5 minutes, depending on size or technique. The article is removed and allowed to cool to room temperature. Subsequent coats, normally different colors are applied. Sometimes many firings are required to bring about the desired results. For fusing enamels to glass, the article is placed into a room temperature kiln and the heat is brought up according to the appropriate firing schedule to the maturation temperature, then brought down to an annealing temperature and held there for a period of time to relieve stresses in the glass, then brought back down to room temperature before removing the article.

Different Flux Characteristics.

2008 – A low expansion clear used as the base coat for the crackle technique when Liquid Form-Water Base enamels are used for the second coat. 2008 is also good as a cover coat when working on titanium white steel panels.
2009 – This soft fusing clear will clear up on copper on the first firing. It may produce “break up” or “pull through” when a subsequent coat of enamel is fired high.
2010 – This soft fusing clear will clear up on copper on the first firing but requires more time and/or temperature than 2009. It may produce “break up” or “pull through” when a subsequent coat of enamel is fired high.
2015 – This medium fusing clear has a gold color similar to Thompson lead bearing 1005 or 426. It works well under warm colors.
2020 – This clear does not “yellow” on silver. It should always be used when a clear enamel is needed on silver as the first coat. It may also be used on copper and gold. It is also the clear transparent that is suggested to be used as a final cover coat in that is has a lower expansion than most of the other transparent clears.
2030 – This clear is the best all-purpose-use clear. It works well under other enamels, opaques and transparent's. Fire sufficiently to dissolve all copper oxide (reddish-brown color). One or two re firings may be required.
2040 – This clear is harder than the above transparent clears. It is least likely to develop “pull through” when applying subsequent applications of enamel. It should be fired sufficiently to dissolve all copper oxide.

How are enamels applied to metal?
80 mesh enamels are applied by sifting through a sifter (a cup with handle and mesh screen in the bottom of the cup). A sifter with a 40 mesh screen is used to apply 80 mesh base coats to metal or glass.

A sifter with a 100 mesh screen in the bottom of the cup is preferable when applying enamel through a stencil. Some sifting stack screens filter out larger enamel particles so smaller grains go through a 100 or 200 mesh sifter.

When sifting enamel, sift around the outer edge of an object first, then move toward the center. The bottom of the sifter should be completely covered with enamel for a more uniform sift. A holding agent such as Klyr-fire used in a sprayer that can create a fine mist will be required when coating a 3-dimensional object. It is best to apply alternating thin coats of spray, then enamel, then spray, then enamel, until an even coat has been achieved. If using a water based holding agent, the water must be dried before firing.

Enamel may also be applied by wetting with water and spooned onto a substrate surface or with use of a spreader or fine sable brush. This is how the Cloisonne, Champlleve, or Acid Etched cavity techniques are accomplished. The trick to successful wet inlay (wet charging or wet packing) is to keep the enamel saturated with water. Too much water or too little water and the enamel is not manipulable. Water may need to be added or wicked out with a paper towel while working. The work is 100% dried before firing.

If water is used in enamel applications as mentioned above, the metal first should be degreased with a surfactant. The easiest method is to heat copper until it flashes with color (annealing to green) but not so long to create black copper oxide. Using Penny Bright is another method of degreasing the copper.

It is important that the primary coat of enamel be as complete and as perfect as possible for the first firing. Faults in the enamel are not easy to correct after the enamel has been fired in place. Unless fire-scale is meant to be part of the design, a sufficient amount of enamel should be applied so that burned out areas do not occur. However, thin coats are better than thick coats. More enamel may be reapplied if the coat is on the thin side, but too much enamel is a bigger problem. Too thick of an application may result in the enamel popping off. As you continue to practice enameling, you will learn what is too little and what is too much. It is important to note that enamel, when properly applied and fired, does not flow out, but rather pulls in toward the greater mass unless gravity affects the movement. If the enamel pulls away from the edge after firing, the cause could be too heavy enamel application.

We suggest that both sides of the metal are enameled. Counter enamel is sold as a mixture of colors, however any enamel may be used as counter enamel. Counter enamel is applied to reduce stress exerted on the enamel by the metal after the piece is cool or during cooling. Counter enamel literally equalizes or counters the pull of the metal on the enamel. The thickness of the metal and the thickness of the enamel are relative in this matter. As the enamel thickness increases, the support thickness must also increase unless other structural considerations have been made in the metal.

Painting Enamels are much more finely ground. They may be combined with a painting medium and applied with a brush. Painting enamels are generally applied to a pre-fired enamel surface.

Liquid Form, Water Base Enamels are formulated to be applied by spraying, dipping or pouring. These liquid enamels have clay in them. The clay allows the coating to ‘set’ after application. If applied with a brush, brush marks may occur.

Liquid Form Brushable Enamels are formulated to be applied with a brush. These enamels can be applied directly to metal or on top of other enamels. Some like to sift a little 80 mesh powder into the wet applied brushable enamel. When the brushable enamel is dried, the surface is quite handleable which allows one to then enamel both sides for the first firing. This is especially helpful to reduce warping when enameling thinner gauges of copper.

Questions to ask if there is creaking or enamel from metal separation.

Has the piece been counter enameled?
How does the thickness of the front enamel compare to the back enamel?
What metal is used?
If an alloy, be very specific as to the alloy.
What size and shape is the piece?
What is the metal thickness?
Is the base metal where the enamel is applied exactly uniform in thickness?
Is the piece flat or domed?
Is the piece cast, metal clay or from sheet?
If cast or metal clay, was the piece designed to be enameled?
Does the enamel have a starting and stopping place i.e. the edge of the metal or a 90 degree angle recess in the metal.
If a recess for the enamel has been created, what is the recess’s depth (for jewelry pieces depth should be .03 to .05 mm deep).
What enamel technique(s) is/are being used?
What is the method of application of the enamel?
How does the thickness of the enamel compare with the thickness of the metal?
What equipment is being used to fire the piece – a torch or furnace?
What is the firing temperature?
What is the length of the firing time?
How long is the piece left to cool?
Where are the cracks in relation to the shape of the piece, cloisonné wires, other inclusions?
What kind of enamel is being used?
What was the temperature of the furnace when the piece was inserted into the firing chamber?
Has the piece been left out (say in the car) in freezing temperatures then warmed up?

Wikipedia's more than you probably want to know about every aspect of Enameling.