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Preventing firescale with Cuprinol


I have been trying to research on the net the most effective way to
prevent firescale when soldering sterling silver. I saw an article
that referred to using Cuprinol. I have only heard of Cuprinol as
wood preservative for sheds and fences etc! Is this the same stuff?
Does anyone else have experience of using this? If so how is it used
in the soldering process? Col

I SWEAR by Cuprinol. It is the best flux I have ever used. I purchase
it in bulk from Rio. I use it in a spray bottle and spray my metal,
heat my metal, spray, heat again, spray, and continue until I have a
good complete coat. It usually takes 2 or 3 heat/sprays for an even
coating. Then I solder. It really does prevent firescale and helps
the solder flow smoothly and easily. I use it on my copper work as
well as my sterling silver work.

I can not recommended it enough!!!


I have not dealt with firescale whatsoever now that I’ve changed
over to argentium sterling. Its only marginally more expensive than
regular sterling but it has saved me loads of clean up time and
hassle. I would highly recommend!


Cuprinol is the wood preservative. Cupronil is the firestain
inhibitor and is made by one of our own Orchid members, Lee Epperson.

Try it, you’ll like it.

No connection.

from cold and rainy Mesa, AZ

Cupronil is a flux
Cuprinol is a wood preservative

James Binnion
James Binnion Metal Arts

Ditto, I use cuprinil exclusively when heating hollow ware pieces or
large pieces of jewelry. I buy it in bulk from Rio. It is a must if
you are working in sterling. I SWEAR by Cuprinol. It is the best
flux I have ever used. I purchase

jennifer friedman

There have been many threads on anti-firescale flux products-
particularly when Firescoff debuted- it’s all ther in the
ganoksin/Orchid archives- Nonetheless, Cupronil has been my favourite
flux anti-firescale product for …well, as long as Orchid’s Friend,
Lee Epperson has been making it! It is simply a great product from a
great company that does all it says it will do: the sprayer is fine,
the product works as both flux firecoaat and layers can be built up
that insulate one’s sheet better than any “ceramic” containing
product available. Cupronil by 4S labs is available from most
vendors, and directly (i beleive) from the manufacturer in a wide
variety of sizes at a most reasonable price. It has remained
consistent since the 1970’s when I first started using it, and comes
from a Hopi silversmith’s recipe- What more could you ask for in a
product? A history of use in silversmithing, consitent performance,
reliable application, wide availability and no chance of a “new and
improved” version being released failing to be equivalent to the
standard on which the company has offered for many years…Buy this
if you have any questions at all about an ant-ifirescale product and
flux in one- that you don’t make yourself (the standby firecoat of
alcohol and boric acid). I recommend it highly to any novices…rer

Nonetheless, Cupronil has been my favourite flux anti-firescale
product for...well, as long as Orchid's Friend, Lee Epperson has
been making it! 

is cupronil available in the UK, does anyone know?

thawed-out wales


If you can’t find it I’d be happy to send you a bottle,


is cupronil available in the UK, does anyone know? 

I was wondering exactly the same thing. I emailed Lee Epperson
yesterday to ask him the question. If I find out I’ll post the
answer - and likewise I’ll be looking out for an answer to your
question on Orchid.


I’m in New York next week. Can New Yorkers recommend me tool and
material suppliers please? Will I need an account? I would like to to
get some cupronil.

Mary UK

I checked with Rio Grande today. They will ship over seas.



Phone Allcraft Jewelry Supply

212 279 7077
135 West 29th. Street Room 403
NY, NY…1001


Hi Mary,

You can go to METALLIFEROUS - 34 West 46th St., NY 10036 - Tel:
212-944-0909 or Fax: 212-944-0644 I am not sure if they carry
Cuprinol but you will have died and gone to heaven when you pick
through their hundreds of shelves of findings, metals, wires, tools
etc. and on the other side of the store is a treasure trove of beads

  • If you have a business bring your tax I.D. - All along 46th St.
    and 47th (the Diamond District) are many tool and supply shops,
    Pearls, gems and jewelery ( too numerous to list) so if you don’t get
    what you need at Metalliferous there are many other stores both
    street level and above. Just look up - If your into bead stringing,
    PHOENIX BEADS & SILVER IMPORT, 5 West 37th St. (bet 5th & 6th Ave.)
    Tel. 212-278-8688 - Fax - 212-278-8919 - The store is awesome. And
    all along 6th Ave. in that immediate area are many bead shops. I
    guarantee that when you hit New York you WILL shop until you drop!

Dress warm - and carry a big bag

Patricia - in New York