IT solder

IT solder users, I talked to Ho my Vietnamese jeweler friend
today and asked him again about the silver solder he uses. He
still makes his own and he told me the formula this time. He
takes nine grams of sterling silver and mixes it with one gram of
pure copper. This as far as I can tell is very similar to IT
solder. He does all his enameling with it. He told me the next
temperature down is eight grams of sterling silver and two grams
of brass. That’s where I got the brass part last time. I do
recall making and using the stuff, but I still prefer refinery
solders. Some great stories about Master Jeweler Ho Trinh some
other time.

Regards,
TR the Teacher (and student)

TR the Teacher (and student).

Seems to me that there are several different formulas for brass,
(from yellow to red, plus different working properties). So the
type of brass used would need to be known for this to be a
viable IT solder. Can we ask again, the type of brass?

John g

A ready source of zinc is in carbon zinc batteries or as a bonus use
U.S. pennies, zinc with a copper plating available at 100 per dollar
most places :-). Bill in Vista

Composition of 1982 cent piece (current coin) : 97.5% zinc, 2.5%
copper. Weight : 2.5 grams. Get new pennies, and weigh the silver and
remaining copper on a carat scale, and you should get IT solder.

Richard (in cold but clear Michigan)

I was very interested to learn from a recent post that the
difference in the hardness of solders is the amount of zinc. Funny,
zinc was mentioned for it’s volatility in chemistry class the next
day. So the zinc gradually burns out—which is why my metals
instructor said that hard solder gets even harder once you have
formed your seam. She said that because of this one can start with
hard solder and stick with hard solder throughout. But if all
solders have a zinc component and the zinc will gradually burn out
in all cases, will soft solder eventually work its way up to hard?
Will hard work its way up to IT? Will soft work its way up to IT?
Most importantly, can one put a partially finished pc, in a kiln at
the burn out temperature of zinc, harden up ones solder and make the
pc safe for enameling? How does one find the exact chemical make up
of their solders—or is this usually a proprietary I
ask because if we don’t know how solders will react to a temperature
gradient, my chemistry instructor should. One more unrelated thing:
Beth, educate me, what does tone mean when referring to a stone?
Me, I love green tourmaline. Marya DeBlasi Columbus OH

First of all, I would like to know of a source for IT solder.

Second, I have found that heating silver solder enough to volitize
the zinc leads to all kinds of pitting in the joint. In multiple
reheatings, you are not heating the silver hot enough for a “purer”
metal to flow in and fill the pits. A pitted joint is weaker no
matter how much “harder” the solder may now be. My real problem is
that I do not believe that the solder gets “harder” as the zinc
leaves. Remember that the purer the silver is, the softer it is!
Harder may be being confused with the higher melting point of a purer
material in this case. Also, to much pickling will attack the zinc in
the solder joint. This ought to be an interesting thread!

I have always understood that there is an alloying or mixing of
atoms at the boundaries of the gold and solder joint and that this
continued alloying will lead to a harder joint with reheatings. I
have come to depend on this trick, or figment of my imagination, to
let me do some really intricate assemblies. (Intricate work was
possible before the laser welder!) Silver solder does not do this. It
joins by flowing into the minute voids in the metal and “gluing” it
all together. Think fingers intertwined. Again, any voids created by
the volitized zinc can only create a weaker joint.

I usually do most of my silver pieces, even the intricate work, with
either medium or hard solder. It is a matter of heat control and
shielding the joints. The solder pic excels here as a heat shield.

Bill Churlik
@Bill_Churlik
www.earthspeakarts.com

Leslie, You can purchase the IT solder from
www.myunqiuesolutions.com. There are lots of different formulas of
paste and powder solder listed on the site. Beth Katz

IT solder from:
http://www.hauserandmiller.com/products/silver/solder.htm

I agree with your reasoning for silver brazing alloys melting at
a higher temperature each time. Brazing alloys diffuse into the
parent metal each time they are melted. This mixing results in a
higher melting point of the joint braze metal.

jesse

I do not believe that the solder gets "harder" as the zinc
leaves. Remember that the purer the silver is, the softer it is!
Harder may be being confused with the higher melting point of a purer
material in this case.

I can see how the confusion arises. Hard can mean “not soft” and it
can mean “difficult.” The solder becomes harder–more difficult–to
melt, so it stays hard–rigid–instead of flowing.

Mark’s post explained the mystery of The Solder That Wouldn’t Melt.
I was baffled by a piece of solder that just sat there, no matter
how much flux and heat I applied. This was on a nearly finished
necklace and I was afraid of melting it, so I applied the torch very
cautiously and backed off too soon. I tried again…and
again…reaching a higher temperature each time, and still the
solder wouldn’t melt. All the reheating must have changed the
composition of the solder so it couldn’t flow.

Janet

when I asked about IT solder yesterday I forgot to also ask about
sweat soldering. If remelting makes hard solder harder should one
sweat solder with easy or medium instead?

Marya Columbus

Janet,

In most cases, the situation you describe, “piece of solder that
just sat there, no matter how much flux and heat I applied”, sounds
more like either a contamination problem with the solder or the
pieces being soldered just were not yet at temperature.

When that happens first, just back off and apply some self-pickeling
flux to the solder and area around it. Bring your torch back and
heat normally. It should flow.

If that doesn’t work, open you flame a bit so it is soft and bushy,
re-heat the entire piece until it is an even dull red then tighten
the flame slightly and concentrate on the join and the area around
it. That should solve the problem.

I tend to agree with those who say that multiple heatings raises the
temp of solder previously applied. However, even with no scientific
data to back me up, I do not believe it adds very much to the melt
temperature.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2

Also be sure to heat the whole piece and do not put the flame
directly on the chip of solder! If you heat just the chip, the alloy
changes as has been noted and may be impossible to melt. It’s not
fun to scrape, file, and sand off a recalcitrant lump.

Marilyn Smith

Hi Bill

Just wanted to say we enjoyed our visit to your studio. Pretty
impressive set up you have coming along. Reading this post, it seems
once again that we think alike on many things. I don’t remember
where or when I first heard of using the pick, but once I did, my
world changed. Not only is it a good way of getting tiny bits of
solder where they are needed, it is a great heat shield, and helpful
in a bunch of other ways for getting a good seam to form on a
stubborn piece. In my early days, I used commercially available
fancy picks with wood handles. The proportions never really suited
me, and I didn’t have the greatest of luck with those. At some
point, though, I realized the some of the ones being sold were just
cut down pieces of welding rod with a point on one end. Now I just
keep a stock of those around, and they suit me much better. Hope to
see you again soon.

Jim
http://www.forrest-design.com

Jim, If you like to get the solder into small places, did you ever
consider using a paste or a powder IT? This is just another
approach and is slightly different from using a pick. You can still
use a pick with the paste if need be to get it into the exact spot
that you want to have solder placement, you could always ball it up
exactly as you do with pallions. One of the wonderful things about
paste solder is that you can place it exactly where you want it
(using a syringe), then go in with a small flame to “set” the solder
in place and then bring on a bigger flame to make the final flow.
With powder solder, you can get the most minute amount of material.
Place flux at the place you wish to have the solder flow, take your
soldering pick, dip it in a paste flux, and then dip in the powder
solder. Small amounts are gathered on top of the paste flux, you
can then go in with the pick as you are doing now. No need to take
the time to cut the solder and get it ready for the pick; it is an
instant way to place it exactly where you want. New and interesting
ideas are always worth investigating.

Beth Katz
www.myuniquesolutions.com

At some point, though, I realized the some of the ones being sold
were just cut down pieces of welding rod with a point on one end. 
Now I just keep a stock of those around, and they suit me much
better. 

Another source of material for making your own solder picks is the
local bicycle shop. They probably have new or old/bent bicycle
spokes. I’ve been able to find a number of old bent titanium spokes
that work really well. They may save them for you if you ask.

Dave

uses IT solder exclusively, smelting his own. 

More nit-picking! Please say, “alloying his own.” The word “smelt”
refers to the chemical process of getting metal out of its ores,
generally with the use of heat.

Judy Bjorkman