Work collapses during enamelling

Hello I’m a student working on my final pieces for the degree show
in Manchester Metropolitan University and wondering if anyone can
help me solve a problem. I am enamelling my pieces and have been
getting problems with pieces I have soldered on before because it
just drops off or collapses, anmd if I solder after I have enamelled
the enamel cracks and break off. Does anyone have a solutions for
this please?

Hi Mari,

It would be helpful to understand exactly what materials and
techniques you are employing before proffering possible solutions to
your difficulties. What are the metals being used for example. The
techniques for copper, silver, gold etc will likely alter depending
upon which materials are being employed. Assuming that you are
employing fine silver for the piece, are you employing IT or case
solder to solder the findings, if you are using hard or medium then
the solder will flow below the melting temperature of most enamels
and the findings will detach or slump.

Are you torch firing the enamels or firing in a kiln, it is
profoundly more difficult to control the temperature during torch
firings and if your piece employs findings with significantly less
mass than the enameled section you would be better served by kiln
firing where more precise temperatures can be employed and the
entire assembly heats at a relatively even and constant rate. Is the
piece counter enameled, if not then a mechanism to support the
findings and the main piece can be employed so that there is little,
if any, pressure on the various components. This can be as simple as
balling up a “birds nest” of binding wire and settling the piece into
it prior to firing, more complex supports can be formed out of the
soft soldering pad materials to the same effect.

While it is possible to solder pieces after enameling this usually
introduces far more problems than it solves, particularly the enamels
can be badly discoloured if inadvertently “flamed” during the
soldering step. You also run the risk of the solder flowing into
unwanted areas of the piece, if this happens to be in the same areas
as the enamel is residing then significant difficulties will ensue
such as blistering, pinging and at the least, discolouration. I am
sure others on the forum will have valuable suggestions to your
current challenges however, in any event, good luck with your
finals.

Kind regards
Don Iorns

... I am enamelling my pieces and have been getting problems with
pieces I have soldered on before because it just drops off or
collapses, anmd if I solder after I have enamelled the enamel
cracks and break off. Does anyone have a solutions for this please? 

You need a solder that has a melting temperature higher than your
enamelling temperature. Also, if you are enamelling over the solder,
it must also be zinc free. Most normal silver solders or gold
solders don’t fit this description. for silver, a solder named “IT”
(perhaps for “intense temperature?” ) is made for just this type of
use, and works well. It melts higher than “hard” solder grades. For
gold, you’ll need to ask your metals/solder supplier for a suitable
grade of solder. The other solution people use is not to solder at
all. Connections can be made cold, using rivets or screws or other
such solutions which would work after the enamelling is done. Or,
joining is done by fusing without solder. This often amounts to using
a modified version of how granulation is done, in order to join the
parts. That sort of join won’t fall apart when reheated. Especially
with gold, you can simply weld joints in many cases, by using a
small hot flame, and tiny bits of the same gold alloy instead of
solder. Smaller than the main pieces, they’ll melt and fuse into the
joint before the joint parts melt. With practice and precise
temperature control and timing, you can get joints almost as neat as
a solder seam in many situations, and after a bit of clean up, you’ve
got a single unified piece of metal.

HTH
Peter Rowe

Hi,

I’m a newbie, but I learned this one the hard way.

The solder melting temperature is below the typical enameling
temperature. This means that when you enamel the piece you melt the
solder.

When you try to heat the piece with a torch to solder it, the metal
starts to expand. It expands faster where it is hotter. This can
cause the enamel to crack because the metal it’s attached to has
become a different size.

The solution I’ve learned is to us a cold connection to connect the
enameled pieces to the rest of the piece.

And from all you experts, if I’ve learned the wrong lesson or you
know a better way, please chime in!

J

Are you using IT solder or just Hard?

Tony Konrath

Mari if your work is collapsing during enamelling my first guess is
that you are getting the piece too hot or just using the wrong
solders. if you would like to contact me offline and let me know what
you are making for your degree show I will give you some tips and
perhaps solve your problems. I have been working with enamels for the
past 49 years and have a lot of experience of what can go wrong, and
I am based in the UK. Check out my work on the orchid gallery

Peace and good health to all
James Miller FIPG

Your problem is the closeness of the melting points of the solder and
the enamel. Ideally you want to fuse your pieces together rather than
solder. To do this you need to have a small amount of a fluxing agent
on the junction of the items to be joined. You can use proprietary
flux containing copper or you can use a wash of copper sulphate. The
idea of this is a local lowering of the melting point on the contact
area as the copper forms a eutectic with the silver. If that is too
tricky then buy some enamelling solder, which has a higher melting
point than standard solder. I make the assumption that you are using
silver/gold for your work. If you are working with silver may I also
suggest using pure silver or britannia silver instead of sterling.
Less oxidation and higher melting point.

Nick Royall

Get eutectic solder. Solders at 1460F, takes lots of heat to solder
but will hold during firings.

None of this should be happening.

Use eutectic solder, which is easy to make - use 80 percent silver
and 20 percent copper - it stands up to firing very well - obviously
you are firing your enamels too hot - check your temperatures. If you
want to play it completely safe, fire to orange peel stage except for
the last firing. If you are being paranoid about it, paint joints
which do not come into contact with the enamel with rouge.

The enamel should not crack when you are soldering afterwards either

  • it’s strange that it cracks, I would suspect that it would become
    very viscose, run and drop off. How to do this depends on the
    distance from what you are trying to solder and the enamel. If there
    is a decent distance between both, say 2 cm, use easy solder and
    solder as quickly as possible. If the solder job is to be done close
    to the enamel, use hard solder (it’s counterintuitive, but it makes
    sense) and solder as fast as you can (with a really hot flame). You
    will locally reflow the enamel where you solder, but it should not
    drop off. Personally, I would prefer soldering before enamelling.
    The best situation is to design the piece so that the none of these
    conditions come up, but it shouldn’t be a problem.

Hi Mari, there are techniques for soldering prior to enameling which
are spelled out in some of the great books on the medium. I am
forwarding this email to the board of the Enamelist Society to see if
an answer can be provided in time for your degree show! The Enamelist
Society website offers a lot of resources for teachers. There is also
a new resource which should be listed on the site…a link to someone
who directly answers individual questions on line.

Good luck!
Marianne Hunter
http://www.hunter-studios.com

You need to use Eutectic solder for enamel. Eutectic solder has a
higher melting point than the melting point of enamel. I don’t think
it is a good idea to solder after enameling, although it may be
possible to re-fuse cracked enamel.

One place that sells it is: http://www.myuniquesolutions.com/

I have ordered from Beth a couple of times and really like her
solders. She has paste, powdered and wire solders. She also has an
excellent explanation of the different types of solders.

No relationship to Beth, just a happy customer. She is a very nice
person.

Sandra
in froggy Snohomish

Need more info from you, what are you enameling on? Sterling silver,
copper, fine silver? And you said collapses, what collapses? If you
have soldered your jewelry and then you enamel the work, I can see it
popping off if you are working on sterling silver with no counter.

Send a photo offline and it will be easier to help.

Patsy Croft

Dear Mari:

If you are going to solder a piece, it is best to do so before you
enamel it. Use IT solder, which flows at a very high temperature so
that the heat from your kiln will not make it flow again. Hard
solder works also for me, but if you use it, check at what
temperature it will flow, then compare that to the enameling
temperature of your kiln. If you are firing at 1450 degrees F, or
1500 degrees F, you should be fine.

It is very hard to solder pieces together after they have been
enameled without disruptinging the enamel. To get the solder to flow,
you need a temperature that is generally high enough to affect the
enamel. Very soft solder does not give as sturdy a joint as you may
need.

When you design a piece that will be enameled, you can plan to use
cold connections in some places such as rivets, bolts, prongs, etc.,
and avoid some of the soldering.

Here is the link to Patsy Croft’s enamel help internet site which
Marianne mentioned in her post:

http://alohilanidesigns.com/enamel-jewelry/enameling-hotline/

Good luck on your final project!

Marcie
Marcia Rae

You need to use Eutectic solder for enamel. Eutectic solder has a
higher melting point than the melting point of enamel. 

Eutectic silver solder has a melting point of 1435 F which is kind of
in the middle of the enamel melting range. The thing about using a
eutectic solder is that it alloys with the base metal, fine silver in
this case and makes a joint that once the solder has flowed will have
a significantly higher melting point than the solder originally did.
It is a tricky solder to work with another option is IT solder which
has a higher melting point and is a little easier to work with

James Binnion
James Binnion Metal Arts

James,

The thing about using a eutectic solder is that it alloys with the
base metal, fine silver in this case and makes a joint that once
the solder has flowed will have a significantly higher melting
point than the solder originally did. 

Thank you for explaining this. At a temp of 1435F I never understood
why eutectic solder was recommended for enameling. It is a “pain” to
work with, but now I appreciate it more.

Jamie

Hi Marcie,

Mari did contact me on the hotline. She was having trouble with the
piece as in her design she was using a vertical copper wire to stack
copper disc on, solder together then enamel, but she stated she was
enameling at 900 c = 1660 F. She sent some photos and you could
understand why it would collapse. She is going to try a SS rod and a
lower firing temp for the enameling. As even the copper disc were
melting.

Thanks for mentioning the hotline. I answer questions all the time
and thought it would be helpful to have them online. Surely someone
sometime will have a similar question. And if everyone shares
experiences we can take this beautiful art to another level. The
easiest way to get to the website is www.enamelinghotline.com It is
very easy to upload a photo with questions or post your own ideas to
share.

Patsy Croft
@Patsy_Croft

As an enamelist, the reason I would choose to use eutectic solder
(silver and copper alloy) is not the melting point (the enamels I use
mature at 1500), but the fact that it contains no zinc as other
solders alloys do (including IT). Enamel will not stick to zinc.
So… if I use eutectic solder to make a bead for instance, I can
enamel over the seam without the enamel popping off. I could also
simply fuse the seam (no solder), but that is even trickier than
using eutectic solder… which is also not so easy as solder that
includes zinc… in my experience at least.

At a temp of 1435F I never understood why eutectic solder was
recommended for enameling. It is a "pain" to work with, but now I
appreciate it more. 

I like eutectic solder because the joints will not give in even if I
fire enamels at very high temperatures, which I sometimes do to
‘burn off’ transparents on top of opaques, but it does not behave
like hard solder. When soldering, it has the tendency to run all over
the place - I always found that strange given that there is no zinc
(which is a ‘wetter’) in it. I often paint a little bit of rouge
close to both sides of a joint that I am going to solder with
eutectic solder in order to confine the solder to a given surface.
For the rest, it is great. It comes close to fusing, but it is still
soldering.

Best regards, Leach

At a temp of 1435F I never understood why eutectic solder was
recommended for enameling. It is a "pain" to work with, but now I
appreciate it more. 

Because it is a eutectic alloy it melts at a precise temperature not
over a range from solidus to liquidus like other solders do. That
means it is very fluid when it melts and you can really draw it deep
into properly prepared joints because it is not a sluggish semi
solid - semi liquid like most solders during their initial melting.
But it also requires more rigorous joint preparation as it absolutely
will not fill a gap in an ill fitting joint. Also because it alloys
rapidly with the surrounding base metal it is fluid for only a split
second, after that forget it, you will not be able to reflow it.

Jim

James Binnion
James Binnion Metal Arts

I like eutectic solder because the joints will not give in even if
I fire enamels at very high temperatures, which I sometimes do to
'burn off' transparents on top of opaques, but it does not behave
like hard solder. When soldering, it has the tendency to run all
over the place - I always found that strange given that there is no
zinc (which is a 'wetter') in it. I often paint a little bit of
rouge close to both sides of a joint that I am going to solder with
eutectic solder in order to confine the solder to a given surface.
For the rest, it is great. It comes close to fusing, but it is
still soldering. 

The reason it has the tendency to run all over the place is that it
goes from totally solid to totally liquid without any intermediate
“mushy” phase where there is both solid and liquid present. This is
the definition of a eutectic alloy and is what makes it so useful in
these kind of jobs but it also is what makes it tricky to solder
with. Any alloy that is not eutectic will have at least a slight
melting range where there is both solid and liquid present so rather
than behaving instantly fluid like water it acts like a slurry of
granular solids and a liquid as you proceed through the melting
range from the solidus temperature to the liquidus temperature.

James Binnion
James Binnion Metal Arts