Soldering red brass / Nugold

I am about to begin a project that is a little out of my comfort
zone. I normally solder silver, but this project is a very large
custom man’s cuff, 6" x 2.5", made of 20 ga nugold (also known as
red brass or jeweler’s brass, 85% copper, 15% Zinc). I will be
soldering a border of 12 ga square wire and 8 - 10 saw pierced
symbols on the front of the cuff, and 6 or more saw pierced symbols
on the back (or inside) of the cuff, all in the same brass.

I am using Dandix paste flux (on the front and back), and 14K easy
solder, which seems to be an excellent color match.

My main concern is copper plating; each time I heat the brass, the
entire piece becomes copper plated. I have been assuming I need to
remove all copper plating before each soldering operation. I’m
wondering if I can get away with soldering right on to the copper
plate, and just clean the piece after all the soldering is
completed? I have been planning to clean the plate by adding
peroxide to my pickle. Also, I noticed some pitting on the underside
of a small test piece. From the look of the back, I’m suspecting
some gunk from my solder block caused the problem, although I don’t
know what.

So with that background, can anyone tell me:

Is there any way to reduce the copper plating that results from
heating?

Must I clean the copper plate before each soldering?

Is peroxide in the pickle the best way to clean the copper plating?

Is there any advantage to using fresh pickle, or a different flux or
different solder surface for this project?

Is fire scale (the deep stain we get with heavily heated silver
pieces) an issue with nugold? (It will have a high-polish finish)

Are there any other tips that might make this brass-on-brass
soldering project go a little more smoothly?

Thanks to all of you, your ideas and tips have truly helped me a lot!
Lisa W.

...14K easy solder, which seems to be an excellent color match. 

True, but when you are finished, and your bracelet slowly tarnishes,
the solder, where visible, will remain a nice bright yellow.

Must I clean the copper plate before each soldering? 

Yes. I feel like a broken record, but the copper color is not
copper, it is red cuprous oxide, which is likely to interfere with
the soldering and must be removed by bright-dipping.

Is peroxide in the pickle the best way to clean the copper
plating? 

It’s probably the safest. Dilute nitric acid (50:50) works faster
but is not very safe nor easy to buy. Either solution accomplishes
the “cleaning,” which is often called bright-dipping.

Is fire scale (the deep stain we get with heavily heated silver
pieces) an issue with nugold? (It will have a high-polish finish) 

No.

Are there any other tips that might make this brass-on-brass
soldering project go a little more smoothly? 

Lisa, please go to the Orchid Archives and look up prior discussions
of brass for other Enjoy making the bracelet. Send us a
picture of it, if possible.

Judy Bjorkman
Owego, NY

Thanks, Judy, for your response.

I have searched through the orchid archives previously, looking for
a discussion about the best solder color match for nugold, and I was
surprised to find nothing. I’ll try again with the general term
brass.

I’ll bright dip between steps, thanks.

What suggestions for solder might work better than 14K? I can always
use silver solder, clean it up well, and oxidize the joins, but I’m
leery of being able to clean up so many solder joins that well. The
symbols to be soldered are like letters, and it will be difficult to
clean up in the tight areas.

Suggestions? I’m all ready to go and anxious to see this project
through.

Thanks for any info!
Lisa Weber

Lisa-

There is a whole other supply chain for non-precious metal welding
and brazing (what we refer to as silver/gold soldering). That is the
conventional welding and compressed gas supply houses. They have many
alloys for soldering brass, bronze, steel, copper, aluminum and so
forth. I bought a big role of silver solder that has a high copper
content and works well with lighter colored brass. They also have
many other brazing rods that will math the color. Look up welding
suppliers in your area. Marlin, in glorious Denver, where the
mountain aspen are turning that magical gold color.