It could be a total disaster for the person using IT to solder joins when planning to enamel over that area in their piece......... IT solder contains zinc.
Let me try it once more. IT solder does not contain any zinc or any
other metals except gold and silver, or silver and copper.
Just because some never heard of it is irrelevant.
Just because it is difficult to use it is also irrelevant.
Just because some books says it contains zinc, does not make it so.
Leonid Surpin
Let me try it once more. IT solder does not contain any zinc or any other metals except gold and silver, or silver and copper. Just because some never heard of it is irrelevant. Just because it is difficult to use it is also irrelevant. Just because some books says it contains zinc, does not make it so.
For every one in the world IT solder is a silver solder composed of
silver and copper and zinc. Beth Katz sells solder to the trade and
is quite knowledgeable in its composition and properties.
James Binnion
James Binnion Metal Arts
Just because some books says it contains zinc, does not make it so.
Agreed. Just because books say something does not make it so.
However, certain books carry a lot of weight (in more than one way.)
Oppi Untracht’s book states that silver IT solder contains zinc, and
that works for me. Perhaps you can cite a reference for your
assertion that IT solder contains no zinc.
Jamie
This is a big powerpoint engineering school presentation on binary
alloys.
Don’t get scared off. it will help you understand much about metals.
It is 90 pages but the key one is page 24 - The copper- silver binary
diagram. A binary alloy may have only one lowest melting point -the
eutectic point. some alloys may have none. At the eutectic point
there is no mushy or pasty zone. it is either solid or liquid !! An
IT solder for silver -copper can be made on either side of the
eutectic point. For silver work this would probably always be on the
silver rich side. Otto Frie has a solder that has a liquid point at
1540 F. this would be an IT solder. There can be many of these but
as the temperature goes up they get harder to utilize.
The diagram for copper -gold is at:
http://tinyurl.com/cw3ujn
This alloy has some changes in the solid state too!
Gold can be a bit complicated to as to match color and carat content
( don’t ask me)
Ternary ( 3 componet ) alloys can also be described the same way on
a triangle shaped diagram, more than 4 componets get hard to study!!
jesse
They use a low brass usually 95 copper 5 zinc called gilding metal.
The is the old US one cent alloy.
To complicate the issue (usually common for “Brass” and Bronze")
some call 90 copper 10 zinc gilding metal.
This brass is commonly called commercial bronze. The nomenclature
system for copper alloys is pretty well fouled up.
Historical bronze is copper-tin.
Historical brass is copper-zinc.
As technology developed, I would say bronze is the base term (and
brass is a copper- zinc subset) for copper based alloys.
As additional alloys were developed they usually were called bronzes
(not always).
Thus we would have silicon bronze, aluminum bronze, manganese
bronze, phosphorous bronze etc.
This is generally true but some of these “bronzes” are called a
"brass" in common use.
Clear as mud ? Know your metal.
jesse
Oppi Untracht's book states that silver IT solder contains zinc, and that works for me. Perhaps you can cite a reference for your assertion that IT solder contains no zinc.
Oppi Untracht’s book also states that white gold contains 25%
platinum or 12% palladium. As I said, there are a lot of strange
things one can find in books. The problem with books is that
everybody
knows everybody, and when someone writes a book, others feel uneasy
to
point out mistakes and so it goes around and around.
About my assertion that IT solder contains no zinc.
For that matter no solder should contain zinc except maybe “easy”. I
belong to the school of jewellery when solder is made by adding fine
silver to the gold alloy used for the project. Since gold alloy never
had any zinc, so was the solder. Procedure was 3 grains per dwt -
hard; 5 grains per dwt - medium; 7 grains per dwt - easy. Alloy was
made a bit higher in gold content to compensate. If joints were
really tight, plumb alloy can be used. Subsequent boiling in nitric
acid, would bring piece within hallmarking range. That is why
jewelers were taught to make tight joints. Tight joints meant
profitability.
Practice of adding zinc and cadmium to solder started when casting
became main technique of jewellery production because casting alloy
do contain these metals. Fine jewellery houses, where problems with
zinc was understood, for hand-fabricated pieces were using IT solders
for precisely the purpose of avoiding zinc. Since I have worked for
Tiffany’s @ Co, I know this is to be the case. IT solders contain no
zinc. IT solders used when one wants to avoid presence of zinc in
finished jewellery. Another use of IT solders is in enameling.
Presence of zinc influences vibrancy and transparency of colors.
Nowadays, alloys are manufactured on the nose (profit before
quality), so melting temperature has to be lowed by zinc, cadmium,
and etc. Another reason I suppose is that soldering is not taught as
before, so zinc crutch became a necessity.
In my practice, I do not use solders containing zinc or cadmium,
except as a last resort in repair situations.
Leonid Surpin
I know most everybody was taught that if it was in a book it was
true. I don’t care who “Wrote the book”.
Eventually you learn to distrust books as well as tv news. Newspaper
news was supposed to be true, but recent times give the lie to that
too.
We do know, I hope, that you can’t trust a politician or a lawyer.
The first lawyer I consulted, I later found, also represented the
other guy.
Look at the phase diagram and see about the eutectic point. It
becomes obvious that you can get a higher melting solder by moving
in either direction.
Zinc is inappropriate on work to be enameled. When you buy solders
you get what you get.
With gold solders zinc is usually (sometimes) added to drop the
melting point from the base material. It makes sense. I try to always
(sometimes miss) give a valid scientific source as well as my view.
Every day the Internet gets more valuable and easier to use–from
home! It will get better still but you need to see where the
is coming from.
One unfortunate fall out of the rising costs of publications is that
the technical journals are not kept at librarys.
But they are available on line from an expensive subscription
service. If you have access to a service-great, otherwise it can much
harder than it used to be, to be really up to date.
jesse
Leonard,
Any formula of solder can be named anything.
There are many who name alloys whatever they wish for the purposes of
their own products; they can then market that product how they want.
For the purpose of this discussion that follows, I am referring to IT
(Intense Temperature) silver bearing solder and not the gold formula.
Please do not quote me out of context.
What is important is what is contained in the solder, not the name
that is assigned.
The statement with the definition of Eutectic is correct, no problem
there. The Eutectic solder contains only two metals for each formula,
if you are talking silver or gold as being the main part of the
formula.
HOWEVER… It is who manufactures the solder as to what
is contained in the solder and their formulation for that particular
product.
I quote your statements:
Just because some never heard of it is irrelevant. Just because it is difficult to use it is also irrelevant. Just because some books says it contains zinc, does not make it so.
In terms of the silver bearing solder, the IT silver bearing solder
in my formulation does contain zinc; I am correct in my statement of
letting people know what will and will not work for the purpose of
enameling over the joins. The majority of those who present IT to the
market place are also putting zinc in the formula so that it will aid
in the melt and flow of the IT solder. It can be a difficult solder
to use as the temperature at which it melts and flows is high, even
higher if it does not contain the zinc.
“Just because some books says it contains zinc, does not make it so”
this is your statement, and as such it is correct… but know what
you are using before attempting to enamel over it and if the product
contains zinc. Most of the solders commercially manufactured today
and sold as IT formulation for temperature considerations (melt and
flow) and content of metals have the common denominator of
containing the zinc if it is silver bearing.
As has been discussed before, it is not a good idea to enamel over
zinc as it can cause a chemical reaction to happen when the zinc
comes in contact with the vitreous enamel. Only if you make your own
solder can it contain whatever you want in the formulation; the
commercially produced solders mostly do contain zinc. Notice that I
did not say all, but only what the solder can do in your projects
when it does contain the zinc.
So, I am saying that if it does contain zinc, I want people to be
aware when they purchase any IT solder that they must ASK if it does
contain zinc.
I am not aware of any major manufacturer who is making a formula of
IT solder that does not contain zinc.
More power to the manufacturer that does make a solder that melts
1345 F and flows at 1435 F and does not contain zinc.
Yes, the IT formula is a high melting temperature solder and there
are many great applications for this high temperature solder; just be
careful. If the formula that you have purchased contains the zinc, be
aware of it and adjust your projects from there.
Again, if you make your own, you can control the ingredients.
Beth Katz
Paste, Powder and now Wire Solder for Jewelers and Metalsmiths.
http://www.myuniquesolutions.com
I am a UK silversmith by training and I had often wondered if what
we call enamelling solder in the UK and IT solder had the same
composition. I also wondered what IT stands for. I asked Richard
Carrano, the Director of Technical Services at Stern Leach, and this
is his reply:
"First the composition of IT solder is: 80 Ag, 16 Cu, 4 Zn
The naming of solders goes way back… before my time anyway, and I
started with Handy & Harman in 1969, by then only the 'OLD TIMERS
were still using that nomenclature. It is my understanding that all
the names are based on someone called 'VANDERBILT". If you assign a
number to each letter starting with 1 for V, 2 for A etc…the Ag
content determines which letters to use…in the case of IT the Ag is
80 so I is 8 and T is 0."
For the of UK readers enamelling solder and IT have the
same composition.
Peter Johns
I am not aware of any major manufacturer who is making a formula of IT solder that does not contain zinc.
That is probably true.
Your definition of IT is Intense Temperature. I do not want to argue
about definition, but it does not ring the bell and I do not remember
what I took IT to mean.
What I do remember is that also was called enamel solder. As you well
aware of detriments of zinc, there is no need to repeat it. What is
obvious to me is that we are talking about two different animals. So
we can put this argument to bed. What I do want to know is the
following. If IT solder nowadays contains zinc, what do people use
for enameling? I mean real enamel, not the epoxy stuff.
Leonid Surpin
Otto Frie zinc free IT enameling solder part # 804.408 - 80 %silver
balance copper.
There is no “intelligent” reason for any zinc addition ! Base could
be a little less silver with a little less mushy zone and a little
lower liquidus point.
Old wives tales die hard.
jesse
Leonard’s Aphorism (theorem):
Just because some never heard of it is irrelevant.
Just because it is difficult to use it is also irrelevant.
Just because some books says it contains zinc, does not make it
so.
Marlin’s corollary to Leonard’s Aphorism:
Just because Leonard says it is true, does not make it true.
I really like IT solder, not sure why. But there are problems with
it as well.
I became curious with the discussion on the composition, and thought
I would look it up in some of my references. I found only a few of my
books even mention IT solder.
Bruce Knuth’s "Jeweler’s Resource Pg 44: says “IT” is 80% Ag, 16% Cu
and 4% Zn, with a flow point of 809 degrees C. Hard solder is 75, 22,
3 at 787.
Oppi Untracht’s “Jewelry Concepts and Technology” pg 394 gives the
same composition and nearly the same flow points.
Mark Grimwade’s “Introduction to Precious Metals”, pg 95: lists
various solders, no “IT” but an “Enamelling” at 71, 22, 7 and melting
range of 730-800 degrees C. His hard solder is 80, 13, 7 at 745-778.
Harold O’Connor’s “The Jeweler’s Bench Reference” pgs 41 & 32 also
does not mention “IT” but has an enamelling solder, without Zinc, as
follows: Ag 6g (80%)and Cu 1.5g (20%) 800 degrees C and a hard solder
Ag 15g (71.4%) brass 6g (28.6%) 750 C.
None of these tables mention a silver/copper eutectic solder (Ag
72%, Cu 28%) by name (many other books did).
Where does that leave us? I think Beth Katz said it best: “It is who
manufactures the solder as to what is contained in the solder and
their formulation for that particular product”.
An interesting thing I found in looking through my enamelling books
is that none of them mentioned zinc free solder and many recommended
traditional hard solder, which all the recipes say contains zinc.
This does nit make it optimal necessarily, but it probably meant
that it worked for the author.
I know that there are literally thousands of formulas for silver
solder brazing filler material. If you look at the industrial uses
for silver solder, you will find a huge body of work.
Bottom line for me - I would choose a eutectic solder or, for a
higher melting point, a mixture richer in silver for enamelling if I
could specify my alloy. Most likely I can not, unless I make my own.
I am too lazy, so I will stick to my “IT” solder for now.
Marlin in sunny Denver
An interesting thing I found in looking through my enamelling books is that none of them mentioned zinc free solder and many recommended traditional hard solder, which all the recipes say contains zinc. This does nit make it optimal necessarily, but it probably meant that it worked for the author.
The reasons why there are should be no zinc in enamel solders are
adhesion and the way zinc affect color.
Adhesion: Smoking is not cool anymore and nobody makes jewellery
pertaining to this habit, but there was a time when cigarette cases
were the mainstay and enameled cases were very popular. If one has to
apply enamel over large surface in thin even layer and has to insure
good wearing properties, the importance of an alloy and dangers of
zinc were quickly learned.
Enamel Color: Anyone who actually handled Faberge enamels knows the
depth of color, the vibrancy and transparency is without peer. The
way those enamels were done was and still remains a secret. But we
have a good indications that alloys and solders contain the answers.
Cartier was the main competitor in this area and dedicated vast
resources, but could not achieve the same results.
Why some enameling books o.k. with zinc? It depends on what kind of
enameling you do. Opaques, small areas, and etc. are much more
forgiving. That is why the issue is not emphasized in some
literature.
Leonid Surpin
Otto Frie zinc free IT enameling solder part # 804.408 - 80 %silver balance copper. There is no "intelligent" reason for any zinc addition ! Base could be a little less silver with a little less mushy zone and a little lower liquidus point.
zinc is added to increase fluidity, reduce porosity as it will tend
to deoxidize the solder and drop the melting point. All intelligent
reasons to add it.
Yes you can solder with just silver copper alloy, I use sterling to
solder things like nickel silver or steel. I have even used it on
fine silver but you better be very watchful as you will melt the
fine silver with the slightest inattention.
James Binnion
James Binnion Metal Arts