Enameling become matte in some areas

Hey There!

I have just recently come across some new problems while enameling
that I was hoping you could help me problem solve. My pieces have
mysteriously become matte in some areas. To be thorough I will
describe my whole process and materials used. I am enameling on fine
silver with non leaded enamels. I am using an acetylene torch to fuse
the enamel. I apply Gum Agar solution as a holding agent before
sifting my enamels. After a few coats I have been soldering posts on
the back of the pieces to make earrings. The pieces are only enameled
on one side. I apply ProCraft Jel-flux and hard solder through the
soldering process. Once the piece is soldered I pickle it in Black
Magic pickle (generally heated pickle but have had same problem with
room temperature pickle too). It is usually at this point that some
of the pieces will have random matte finishes on the surface of the
enamel. I have also used white-out on the solder joints to re-heat
the piece to try and fix the matte finish so as to rescue the piece.
These are all processes that I have utilized before without any
problems whatsoever. Maybe it was just luck and there is something I
am using that is an obvious offender to my dilemma. I am feverishly
preparing for many craft fairs and need this problem solved so please
give me any input you have.

forever grateful,
Kim O’Brien aka k.o’brien jewelry
http://kobrienjewelry.supermarkethq.com

Kim, Most likely your enamel is not acid proof, or acid resistant.
Some of the old lead bearing enamels are more sensitive to the acid
and will lose their gloss. Always test your enamels first to be sure
that the colors you are working with will hold up. Some of the colors
are fine, others will become matte.

I doubt that the temperature of the pickle will make much
difference.

Alma

It’s the pickle! You should finish all soldering before you enamel.

If this is an impossibility then regrind the surface of the enamel,
thoroughly wash and then quickly re-fire the enamel using rouge
around any of the soldered joints to stop re-flow.

hi kim,

i know that pickle can matte the enamel. i’m a torch-firer and have
had it happen to me also. i make sure that i do not have to pickle
after soldering. i also have soldered earlier on than you, with no
problem during torching. i have used hard solder also when working
with silver. i just keep fluxing any silver areas that aren’t fine
silver and then use water to remove the flux in the end. i have also
noticed that a couple thompson colors don’t enjoy torch-firing on
fine silver as much as others. no problem on copper, but fine
silver–a different reaction. i could not say why. just observation.

don’t know if this helps.
anne

Are you using transparent or opaque? Some enamels don’t react well to
pickle and get “etched” on the surface causing matt finishes.

Kim,

As everyone else suggested, it sounds as if pickle solution might be
the culprit.

In order to prevent this problem I usualy make a small sample of the
new enamels I acquire to see how they react. I do it on a thin sheet
of silver and use a piece of gold paillon in an erea to have a
sample of the color on gold and silver as the metal under the enamel
will sometimes drastically influence the end result in transparent/
translucent/ opalescent colors.

I also keep the sample for further reference with the name/number
and company that manufactured the enamel on the back of the sample
and put PS (pickle sensitive) annotation if it is…

As a general rule it is not advisable to pickle a piece after
enameling.

Cyrille

As everyone else suggested, it sounds as if pickle solution might
be the culprit. 

Powdered vitamin c, ascorbic acid, can be used as a pickle, it will
not damage the glass enamel.

Richard Hart G.G.
Denver, Co.