Stainless vs. carbon

Since we are on the subject of steel shot, I have a question...I
have run across 2 different opinions on my jewelry travels;
those who remove the shot from the tumbler EVERY time they use
it, dry it and store it and those who leave it in the tumbler
covered with water and tumbling solution. I prefer to leave it in
but dont want rusty shot. Any opinions? I have an economy rotary
tumbler from Gesswein

Jennifer-

As I said before, we remove and clean the steel shot everytime
that it is used, but we also use several different media to
tumble polish. The soap is in a reservoir that circulates and is
only ocassionally changed and at this time it is sent to the
refiners after going through another process to extract the gold
out of the solution. We also use the ceramic shot for fast
cutting, walnut shells, etc. from time to time. It depends on the
amount of hand polishing the piece will require. The main thing
is to keep your shot from rusting, which ever way that you do it.
I have tried both ways, and this is what works best for me. You
dont have to discard your solution, it can be re-used, so it is
just a matter of removing the shot while it is not in use. Hope
this helps you! Ricky Low

Hi John,

Thanks for the info (filed away) and for the philosophy. I
don’t quite see it your way - but, with all due precautions, I
can see that the acid route would probably be a less wearing way
to go.

Nina
Nina - Silver Design, 9122 S. Federal Hwy, Suite 249,
Pt. St. Lucie, FL. 34952 : Toll Free:1-888-460-1800
URL: http://www.nina-sd.com : Email: @Nina

It has to do with if the alloy is martenistic or austenistic,
if I remember correctly.  Anyway, I understand that you get
tempered steel by the creation of martensite in the steel
which is magnetic (speaking strictly of high-carbon >steels
here).  With the stainless alloys you acheive this by
work-hardening and you're creating the martensite, which is
magnetic.

Hi Rick,

Martensite is created by thermal activity, that is when the
steel is heated above - well, depends of the amount of carbon -
750 C - 800 C, and quenched. At these temperatures, the
iron-carbon-alloy has an austenite structure, that is, a
cristallite structure of cubic iron where atoms of iron and
carbon are on the corners of a cube and in the middle of its
planes. When this structure cools down slowly, the structure
changes to one that has atoms only on the corners of the cube
and one in the middle of the cube, which is called ferrite. With
all these structures, the ability to dissolve the carbon is
different, and surplus carbon becomes cementite, which is iron
carbide Fe3C. When the steel is quenched quickly enough, the
ferrite doesn’t develop, instead the structure changes to a
tetragonal one with one atom at each corner and in the middle of
it. As this is oversaturated with carbon, ther is a lot of
tension in the cristalline structure, hence the hardness and
brittleness. Martensite can be created by inducing a tension to
certain alloys, this is also called super elasticity, but the
martensite is re-transformed, when the tension is taken away.
The memory metals belong to these alloys.

Regarding stainless steel and magnetism: If there is nickel in
the alloy with more than 7% and it has high chrome content,
austenite structure is stable unto below room temperature, and
are virtually not magnetizable.

Stainless steels that are hardable thermically :

carbon 0.2%, chrome 13% (Euronorm X20Cr13); carbon 0.3%, chrome
13% (Euronorm X30Cr12); carbon 0.45%, chrome 15%, and small
amounts of molybdene and vanadium (Euronorm X45CrMoV15); carbon
0.12%, chrome 17%, small amounts of molybdene and sulphur
(Euronorm X12CrMoS17). Sorry, don’t know the US (SAE)
denotations.

Lots of bone dry theory, eh?

Markus

G’day; my suggestion (for what it’s worth because I’ve never had
to do it) is to put the work into a approx. 50% slightly warmed
solution of nitric acid: sterling and fine silver dissolve easily
and rapidly but gold doesn’t; aqua regia or cyanide is needed to
dissolve gold. I know: nobody likes messing with acids like
nitric, and the gases given off are nasty too (nitric oxide and
an aerosol of the acid itself) But like they say, when you gotta
go you gotta go!

Dear John and Nina:

You might want to try to the same trick I use when I have a
firestain problem- you can try having your gold piece plated gold
to hide the silver that got on your piece…

DeDe

DeDe Sullivan
Producer
Manhattan Transfer Graphics
Tel: 212-907-1204
FAX: 212-370-9346
E Mail: @dede

Hi DeDe,

Thanks for the suggestion. I wasn’t trying to get rid of
firescale but to remove metal overplating from putting my stuff
(retarded moment) in the wrong tumbler. I keep two tumblers -
one for gold and one for silver - and if the piece goes in the
wrong one it overplates. John’s suggestion was for removing
that.

My question was - what do I do with two-color work. What do
other list members do - got to be able to clean it up after
pickle somehow.

Nina
Nina - Silver Design, 9122 S. Federal Hwy, Suite 249,
Pt. St. Lucie, FL. 34952 : Toll Free:1-888-460-1800
URL: http://www.nina-sd.com : Email: @Nina

Nina:

I would love to help you! Can you please explain your problem in
detail for me? I combine silver and gold alot (it that what you
mean by two color work?). When I solder I am very careful not to
make a mess of it (letting silver or gold solder glob on places
it shouldn’t…)

DeDe

Regarding the grey-ing of silver tumbled in stainless shot- this
happens after extended tumbling, yes? Sounds too simple, I know,
but put some squirts of Dawn dishwashing liquid in with clean
water and tumble for ten minutes, then rinse. The water will be
dark. Repeat until the water runs clean and the shot & silver
are no longer coated. Shouldn’t take more than an hour to get
the goop off. Don’t know what to do with carbon shot, but this
works for stainless. -Dana

Hi DeDe,

Boy, doesn’t anybody ever go to bed around here? It’s 2.37 a.m.
and I’m sitting here working on my newsletter and the old Eudora
is chiming like a mad thing. It’s all Orchid. Must be jewelers’
syndrome or something, this night owl thing.

Yes, that’s exactly what I meant - the combination of gold and
silver in one piece. My question was how to tumble the piece
after it comes out of the acid. Each metal will deplate to the
other and I have no idea which of my two tumblers (silver or
gold) to use. Have to tumble to get all the crap off -
otherwise, I have no idea. I can polish out on the wheel but
not straight from the pickle - it doesn’t get in corners and in
the backs of rings, etc.

Another option is to start a new tumbler (I have one which I use
for investment removal solution) and hope that the shot doesn’t
impregnate that quickly that it will deplate the metals to each
other.

What do you think, lady?

Nina

Dear Nina:

This is a tough one. I am going to see the women who taught me
99% of what I know in two weeks and I am going to pose this
question to her…I usually don’t tumble most of my work. In the
pieces where I mix gold and silver I hand finish. - and believe
me it gets pretty creative…I usually “Make” the tools I need to
get into hard to finish areas (I like matte finishes) Like I will
tape or rig sandpaper on objects to get into hard to reach areas
(like tooth picks or small files…)or carve a blue wheel to
suit my purposes when I use the flexible shaft. I am sure my
anwer does not help you but I will come up with a better anwser
in a couple of weeks…

DeDe

DeDe Sullivan
Producer
Manhattan Transfer Graphics
Tel: 212-907-1204
FAX: 212-370-9346
E Mail: @dede

Daryl,

Boing!!!.. Your note may have just woke me up!.. are u using
what I would call a ruff stone, small black rubber tumbler …
sorry but like a small ‘toy’ tumbler for kids … with stainless
’shot’ to polish ??? If so… for both gold and silver?? Really
could do the same as Silver polishing by hand … destroys the
take home…

Jim