I have a piece in 22K gold that I have enameled in many places. I’d
like to melt it down and cast something else. Does anyone know if the
enamels will mess up the melt, or will they just rise to the top like
borax and not affect the gold? They are leaded enamels.
Larry
Larry, It might be better to remove the enamel. There is a recipe for
removing enamel from metal in one of this year’s back issues of Glass
on Metal. It will then leave your metal clean for melting.
Alma Rands
I have a piece in 22K gold that I have enameled in many places. I'd like to melt it down and cast something else. Does anyone know if the enamels will mess up the melt, or will they just rise to the top like borax and not affect the gold? They are leaded enamels.
I’ve never let this worry me. I would just go on and ignore the
enamel. Perhaps hit it with a hammer to break out the majority of
the enamel. Melt and cast. If it forms brittle metal or some other
problem, mold the work and cast with new metal. What can you lose?
Bruce Holmgrain
JACMBJ
They will very likely contaminate your metal and render it scrap,
don’t do it. Even though the metals in enamels are bound up as oxides
the possibility of reducing some of it when molten it too great. It
takes an amazingly small amount of lead to ruin gold alloy and make
it fracture when worked.
Jim
James Binnion
James Binnion Metal Arts
Hi Larry
Good you asked. No the enamel will more than likely sink into the
surface. Don’t cast with enamel in it.
There are others who can tell you what acid to use to dissolve the
enamel first.
David S. Geller
JewelerProfit
Should not be a problem, that said lead oxide was one of the first
metals reduced from ore in a fire (strong reducing atmosphere), so to
be on the safe side I’d recommend an oxidising flame.
Now for the weasel words: I haven’t tried it so am only speaking
from theory, lead in gold is a bad thing period, so it might pay to
remove as much of the enamel as possible before you start melting
things…
Cheers, Thomas Janstrom.
Little Gems.
http://tjlittlegems.com
Larry, It might be better to remove the enamel.
Sounds like the safer course to me. If you heat the piece to, say,
1000 degrees or so and then toss it some water, the enamel should
shatter and fall off.
Noel
Thank you for all the warnings, folks. Someone suggested that I heat
the piece red hot and dunk it in cold water to remove the enamel.
Will this work?
Alma, would you know where I should go in Glass On Metal to see this
Larry
I just learned the best method for removing enamel, thanks to an
email I received from Bill Helwig at Thompson Enamel… The
instructions are in the Thompson Enamel Workbook, and it involves
submerging the piece in lye (contained by a stainless steel bowl),
then placing the bowl into a kiln at 750 degrees F. Supposedly, in
about a half hour the molten lye will have melted off the enamel,
and the piece can then be removed with DRY tongs and rinsed in water.
The book says that this is the best and fastest method for removing
enamel.
So tomorrow I buy the lye and give it a try!
Thanks again for all the kind suggestions from everyone.
Larry
This works like a charm. I tried it last week on 3 pieces. Anyone
that works with enamel should write this “recipe” down in their
little journals and never lose it!!! Seriously!!!
Mix equal parts of Salt and Cream of Tartar…now take some water
and make it into a creamy paste. Place this mixture all over your
enameled piece. Heat your piece in the kiln at 1425 or so for 2-4
minutes. Take your piece out of the kiln (don’t worry…the piece
will be black…this is normal) and immediately drop it into a
container of ice water. Use a steel brush to remove all enamel. This
process may take a time or two…however when I did it I was able to
get all my enamel off all my pieces in the first try.
I LOVE this recipe. It “saved” some of my very old pieces that I was
going to scrap. BTW…I did this with silver…I’m assuming it will
work on gold too!
Good Luck!
Aimee Domash
And so we ALL learn something! Have to remember the lye trick,
sounds way easier than heat and quench.
Cheers, Thomas Janstrom.
Little Gems.
http://tjlittlegems.com
Larry, It is in the Dec. 2007 issue of Glass on Metal, in an article
written by Pam East, who got the from Priscilla Vasso,
who in turn learned it from Gilberto Maxxotti of Brazil. So, this
wonderful hint has been passed around.
Now, I do hope those who are reading this will get Glass on Metal
and read the whole article, but for those who need immediate
assistance in removing enamel from metal, here is the proceedure.
It is very simple, safe, and effective. All you need is to mix equal
parts of table salt and Cream of Tartar (which you will find at any
grocery) Add enough water to make a thick paste…
Apply the paste to your enamel, covering it completely. Place the
piecein your preheated hot kiln and fire it for 2 minutes. It will
smoke and turn black. Remove your piece from the kiln, and drop
immediately into a bowl of ice cold water.
I have not tried this, but have been assured that it works. The only
thing I have been puzzled about is putting the wet mixture into the
kiln.
The article does not specifiy that it should be dried first. Also, I
see, from the picture in the article that Pam uses a small table top
(beehive) kiln, not a big kiln, so combustion should not be a
problem.
At any rate, try to get a copy of the article as the pictures are
very helpful. Hope this helps.
Alma Rands.
There is another and less caustic way to remove enamel than using
lye. It’s in my book, Enameling on Metal Clay, but the method should
work fine on any metal. Mix equal parts cream of tartar and table
salt. Add enough water to create a thick paste. Apply the paste
liberally over all the enamel and then place it in the kiln at 1450
degrees F for just a minute or two. Leave it until the paste is
completely blackened and glowing a bit underneath. Pull it out hot
and drop it in to a bucket of cold water. All the enamel should come
right off. If there is a lot of enamel, you may have to do this
twice, but it the method works really well and is easier to deal
with than lye IMO. This method of enamel removal is not without it’s
affect to the metal, but since you’re planning to melt it down anyway
that shouldn’t be an issue. I’ve got an article about the more
lasting effects of de-enameling coming out in Art Jewelry Magazine
next year some time.
Pam East
I have reused enameled gold after these two steps:
Removing most of the enamel be hammering with a metal hammer on a
small iron anvil.
Heating the piece till it is red and quenching in water to remove
remaining enamel.
Lois
www.loismartens.com
Have to remember the lye trick, sounds way easier than heat and quench.
Seriously? You’d rather mess with corrosive chemicals than use a
little heat and water? Huh!
Mix equal parts of Salt and Cream of Tartar...now take some water and make it into a creamy paste. Place this mixture all over your enameled piece. Heat your piece in the kiln at 1425 or so for 2-4 minutes. Take your piece out of the kiln (don't worry...the piece will be black...this is normal) and immediately drop it into a container of ice water.
Did you try this same routine without the paste? Bet it would work
just as well. What do the salt and bitartrate have to do with it?
Noel
So tomorrow I buy the lye and give it a try!
Some time ago, I was experimenting with removing platinum investment
with molten lye. I dropped the work in pickle while it was hot and
caused an explosion. I repeated the experiment. Molten lye and water
are not to be toyed with. Lye is nothing to be trifled with. BE
CAREFUL!
The instructions are in the Thompson Enamel Workbook, and it involves submerging the piece in lye (contained by a stainless steel bowl), then placing the bowl into a kiln at 750 degrees F.
Larry, I’ve known that for years, and have never posted it
(including this thread) because it’s extremely dangerous. The lye
must be absolutely devoid of water, and anything involving it must
be absolutely dry. Absolutely. Or the lye will “explode” all over
everything…It’s the recommended method, just be very, very
careful and have full ventilation, too.
I would remove the enamel 1st. I just used this method for the first
time one month ago. It worked perfectly! Use equal parts of table
salt and Cream of Tarte. Mix in a few drops of water at a time until
you have a paste. Cover the enameled area with the paste. Return the
object to the kiln at the same heat and time you used with the
enameling process. When you timer goes off, remove the piece and
immediately plung it into a bowl of ice water. That’s it. Sounds like
voodoo but it works like a dream. You can get the cream of tarter at
any grocery store in the spice section, if you don’t already have it
in your kitchen.
Linda
Seriously? You'd rather mess with corrosive chemicals than use a little heat and water? Huh!
If it gets rid of 100% of the enamel then yes, I have no real
problems with the chemical handling and storage involved (chemistry
background among others). With quenching there is always that last
little bit to remove by other means.
Besides I already have the kiln, and lye is relatively safe (and
easily available) (for a given value of relative), if you remember
not to get it on your skin or on to anything else you want to
keep…
I’m not belittling the dangers, just that I’m ok with them in this
application, one thing to remember is that by the time you’re
finished with this process you can guarantee that your lye is
anhydrous, and so all the more reactive to water, so NO SKIN contact
period.
Cheers, Thomas Janstrom.
Little Gems.
http://tjlittlegems.com