I have a problem that I need help with. I have some surgical steel
wire that is imbedded into some fused glass pieces and has turned
black from heat oxidation. Can I dip it into one of the name brand
“Silver dips” and bring it’s sheen back?
If not, what are my alternatives( polishing wheel is not time
effective)?
Regards,
Andrea Streicher
Striker Studios
Original Sterling Silver and Fused Glass Jewelry
510-528-3755
www.strikerstudios.com
I’m afraid that darkened color on stainless is rather difficult to
remove. I have used it deliberately for color contrast in some
forged, leaving dark resessed areas and high-polishing the high
areas. I’ve found it to be a remarkably durable oxide. Perhaps
there are some acids like hydrophloric that would remove it, but that
one is perticularly dangerous and it would no doubt leave a matt
finish as it etched the surface. Plus, I don’t know (John Burgess
could tell you) what gasses would be released by the hydrophloric and
the nickel in the stainless reacting, possibly nitrous oxide, not a
good one to be exposed to. Perhaps you could mask off the glass and
use a sand blaster with a glass bead abraisive. You might also try
brushing with a fiberglass brush (but take care with that, as it
sends minute particles of fiber glass all over, itchy stuff, and
regarded as carcinogenic by some). Good luck, I’m sure the others
will have some suggestions.
David L. Huffman
G’day; I can state quite categorically that hydrofluoric acid cannot
produce nitrous oxide from stainless steel - or even nitric oxide. I
can find no on reactions between stainless steel and
hydrofluoric acid, and have no personal knowledge of a reaction.
Contrary to popular belief, HF isn’t really what one might call a
’powerful’ acid; it does react with human (and non human) flesh
producing ulcerous burns which don’t heal very well. It also
dissolves glass, quartz and silica, which no other acid does except
in minute quantities. It dissolves or reacts with a very few things
at all. Most metal fluorides aren’t too soluble in water anyway.
Superheated water at very high pressures does, go for stainless, but
then that reacts with literally everything - it is the Universal
Solvent the ancients were looking for. How else do agates and other
hydrothermal minerals get produced in nature? It even dissolves
gold and platinum, then deposits them when pressures and therefore
temperatures are reduced.
Boiling stainless with 10% sulphuric acid might remove the oxides
from heated stainless. Otherwise old fashioned abrasives will have to
do Cheers, –
John Burgess; @John_Burgess2 of Mapua Nelson NZ
Thanks, John; I appreciate the info on hydrofluoric acid. Much more
than I knew before, although I may not have many occassions to use it
(divesting platinum, perhaps). But it will come in handy to know
that oxides might be removed from stainless with 10% sulfuric. I’ve
always figured abraision was about all I could do. Doesn’t work when
you’ve got areas you can’t get at, however. And I do, quite often,
work in stainless.
David L. Huffman
I think
6HFl + 2Fe = H2 +2FeFl3 ?
Hydrogen Fluoride + Iron = Hydrogen gas + Ferrous luoride
is the reaction formulae
No nitrogen in the acid thus no nitrous oxide.
Some bright dips do contain a proportion of Ntric acid. This will
produce nitrous and nitric oxide.
Makes sense to me anyway.