Test firing strips for enamels

Jewelry Discussion
1

I have some questions about making enamel color test strips.
Transparent lead-free colors over 22 gauge copper, fired with a
torch. I’m thinking of doing five swatches: direct onto the metal,
over clear, over opaque white, over silver foil, and over gold foil.

Have I left anything out? How do I attach the foils? And how many
firings do I need? Can it be reduced to just two: the clear and the
opaque white as one firing, then attach the foils and sift the color
over the whole piece and complete it in the second firing?

2

To produce what you describe as “test” pieces needs equipment much
more accurate and controllable than just a gas torch.

Apart from the enamel preparation, application, and counter
enamelling, you need to be able to record temperature and heating
time.

Torch firing is notorious for messing up the atmosphere over the
enamel.

just try it and see what happens.

An electric oxidising atmosphere muffle running up to 1000 deg C
with pyrometer display and control as well as a peep hole is the way
to go.

But before you do any of that, You need to ask the following
question, where can I find out ALL the about enamelling
that exists, in order to read it all up? Because all your questions
are answered in books on the subject.

Libraries, metal working colleges, book shops etc.

DO your research first. It will save you a lot of time and heart
ache.

You need to really understand the principles in fusing glass to
metal as well as practicing the techniques.

Have fun.

3

Hello Marie,

Google Open Studio - Grains of Glass Enamel Artists this is a website for
enamelists and those interested in learning more about the process.

I did 4 tutorials on torch firing of enamels. One is about the use
and sgrafitto of gold and silver foils. You do not have to join this
site unless you want to comment. Several members have submitted some
very usefully on various enameling techniques. I hope
this can be of help to you.

Best,
Chris Hierholzer

4

I apologize, Ted, if my question was too basic for this group. This
is a great resource and I’d hate to gum it up. However, in my
defense: I have done some research. I have two books. They both
recommend test firing strips, but are vague on the procedure. And
they both recommend that newbies begin with a torch, not a kiln, so
they can directly observe the changes in appearance.

5

Checking in after awhile mia. I didn’t see the question, but the
advice good. May I suggest also: contacting the The Enamelist
Society to find a possible local guild/group. You’ll also find
suppliers. One thing about the test strip/ torch firing question. if
it’s your intention to continue to use your torch to fire enamels,
then your test strips should be with that tool. If you’re going to
get a kiln and use that, then you’d be better off waiting unless you
don’t mind repeating the exercise. (wish I had a the patience to make
myself a whole new set that includes all the colors/manufacturers I
have now). All these years later, I’ve still never timed a firing,
but that’s just my lack of organization. Works for me but it’s not
for everyone. Good luck.

Marianne Hunter
hunter-studios.com

6

Marie, where are you located? I agree with Marianne. Test with the
tool you plan on using

Jennifer. Harris. (Friedman), Enamelist
Now in Pearland, TX

7

Make sure your piece of copper is clean-no grease, etc. You’ll be
working in strips/stripes across a piece of copper. Cover one strip
so no enamel gets on it-paper, card, whatever. Next to that you can
put a strip of white.

Sift clear flux, like Thompson’s 2020 (clear for silver) or 2040 a
hard clear, over all the rest of the plate. Note: with lead free
opaque enamels, we find that putting down a layer of clear first
(and fusing it) makes for a smoother opaque layer, but it isn’t a
hard and fast rule.

A 3 x 3 piece of copper will allow you to do 4 or 5 or 6 colors on
the same plate, once prepared. Torch it to fuse the ‘clear
transparent layer’ (torch from the back side). Air cool. Clean off
the oxides. Leave a strip of bare copper, a strip of opaque white
(Thompson’s 1060-opqaue and very white is a good choice) and then
clear enamel sifted over the rest or you can ‘wet pack’ (allow to
dry before torching). Next, on top of the now mature areas of clear
enamel, lay a strip of silver foil, which tradition says has been
lightly perforated to allow air to escape (between 2 sheets of sand
paper works) over brushed on water or water plus Klyr fire solution
or your choice. Foil is very light and tends to lift.

Last strip is gold foil, fixed & all dried. Fire all this to
maturity. The foil strips will be then tacked onto the base layer of
flux at this point.

MOST of the time, a layer of clear enamel is fired over the silver
foil.

Reds, oranges, some yellows can react poorly with the silver. A layer
of clear protects but allows the transparent color to shine
beautifully. You would sift the clear over the silver strip and fuse
it. Clean off those oxides again. NOW you are ready to choose
transparent colors to sift or wet pack over all the strips (cross
wise), maybe half an inch wide? Or an inch if you need a broader
sample. You do need to clean your transparent colors first. A small
amount of color covered with distilled water, let it settle a
little, pour off the cloudy water. Repeat until you have no clouds.
Or if you have graduated sifters, you can sift one color to 150 grit
and then wash the stuff that collected in the 150 mesh. It can be a
little speedier.

You will use the color test plates over and over in your career, so
be as careful as you will doing a project piece.

Eileen Schneegas, Snow Goose Designs