Forming striped gold sheet

I’m looking to get some opinions/ideas on fabricating two color
striped metal sheet. My dilemma is whether to solder strips of
gold/silver together or to use my furnace to fuse the strips into a
sheet. My intention is to use thesheet as a basis for making a watch
case back and bezel. Would soldering orfusing strips together be
stronger? My mind is leaning towards laying alternating metal strips
on a backing of silver or brass, and then putting them between torque
plates in my furnace(similar to how mokume is sometimes formed). The
forging method is more complex than hard soldering the strips, but
for some reason I tend to think that soldering wouldn’t hold as
strong, is that true? Would a properly soldered piece hold up to
subsequent shaping into my final piece? I would appreciate any
pointers from anyone who has done anything likethis.

Erik Savoie

I can tell you whatworkswell. I made a design of a contemporary
bracelet, as follows.

Stainless steel back around 1.5 in wide.

then a brass strip 1in wide then a copper strip 1/2 in wide. all
around 35/1000 in thick.

I hard soldered then all together, as a laminate, then concaved the
strip then formed it around my bangle mandrel.

all the metals followed the curves without breaking.

Looked good.

Note, the stainless base is hard the brass half hard and the copper
soft.

It didnt work well the other way, so use the hardest as the base.

It was tricky getting the solder to make a proper contact all over
each metal.

What do you use for solder on Stainless steel, I have some steel
wire, like to make jump ring out of them, could you give me some
lesson on soldering steel? Thank you.

Anna

What do you use for solder on Stainless steel, I have some steel
wire, like to make jump ring out of them, could you give me some
lesson on soldering steel? 

For hard soldering ordinary mild steel and s/steel as in silver
soldering of silver, your normal silver solder is fine.

For silver soldering stainless steel, such as 316 grade (18 nickel
and 10 chromium) you need johnson matthey stainless steel flux.

Use this flux on the mild steel, and for every other fluxing as
well. Just one flux will then do everything.

For soldering the jump rings true up, place the silver solder
paillion,10/1000in thick piece no thicker! in between the ends of
the ring, flux, heat then drop in the pickle. Run some trials with
rings before you do the ring on the finished piece to get the
technique right.

The thermal shock will crack off the flux.

you will need to boil it in water anyway to remove the last of the
flux residues.

You will find making s/steel jump rings in say 1mm and thicker hard
on the hands.

The trade off is its very much stronger than silver.

Hi, Anna -

One alternative might be products made by the “Muggy Weld” company.
They have a solder paste that looks interesting

I’m not affiliated etc. etc. and if I’ve broken the rules by
mentioning a company or product, I’d appreciate if someonelet me
know! Thanks, Bob

Addendum: with a furnace if you want the contrasting colour to go
through to the same depth fusing is necessary but you must pay close
attention to the liquidus points of the metals you choose to work
with. It is far easier to solder inlay or forge a wire of a
contrasting colour into a backing and then roll it out to the gauge
you desire. Forming is no problem with either method. Again,
undercutting a bit helps hold a contrasting strip/wire into the base
once rolled out with or without heating/soldering it to bond them
further. I have had excellent results inlaying brasses into silver
as well as copper and other alloys both with and without heat. I have
never had delamination or a returned custom item in over 30 years.
rer

Inlay works well and is less problematic than fusing depending on
the metal combination you want to work with. Simply clean the metal,
carve, using a bur, bits or gravers to make your design. then use
only plumb solder in contrasting colours or metals to fill. Karat or
colour doesn’t matter unless you are using a low karat gold as the
backing- then it can be tricky, but I’m presuming you aren’t using
anything like 9-12 Kt gold as the backing. It has worked well for any
combination I have ever tried. Using a heavier base if the melt flow
point of the solder is higher than the base metal is the only
consideration. Also this method is for designs that are not terribly
wide or deep relative to the base. Once completed a quick trip
through a rolling mill finishes it absolutely flush without
reduction of the size you wanted. Using silver as a backing/ base
with any contrasting metal will work well first time!

The other option is setting a wire into the grooves you create for
the design. you have to be somewhat more exacting but for a bezel it
is straightforward. Use the thickest base possible and the
contrasting metal doesn’t have to be 1/2 as deep as the backing. Once
pounded in or rolled into annealed metal (comes out cleaner without
reducing the overall base depth just rolled enough to flatten or make
the wire flush with the backing metal) it requires only a finish or
matting if not some other texture you like. No undercutting is
necessary with a wire and a quick fluxing of clean base metal and
heating is enough to bond the two if you are worried about the wire
popping out for some reason (i have never had this happen).

Fusing a contrasting metal can present a lot of problems from
burning through the backing to holes melted through from heat
concentrated a bit too long along the design. Solder filling is the
easy way to go if you haven’t got access to a rolling mill. Heating
from underneath with a tripod helps warm the metal and liquefy the
flux with the solder inlay method and if you can work fast is the
best way to go. I have used up to 22kt rich/royal yellow (but always
using fine silver if silver as a base metal) without problems. If
wanting copper contrasting with silver lay the copper into the silver
to prevent any skin reactions. Same with any alloy containing nickel-
put the nickel containing alloy into the silver or Pt, Palladium or
Fine gold (if using a coloured gold on a yellow gold back)…if you
have further questions feel free to contact me… rer

Karl Fischer (sells a solder for stainless steel for about 6 bucks
called “GOBA”.It can be used with all base or precious metals and
they sell a product called Oxynon that is strictly for base metals.
Also when using stainless steel remember you 'll need Sparex # 1 as
a pickle as the common #2 won’t work or use another brand/substance
like Vitrex brand powder (sold by fischer) which does require safe
handling as it can fume a bit when fresh and is a caustic salt but
can be used with precious and non-precious metals. There is always a
peroxide or citric acid but they require a strong concentration
compared to that used for precious metals( non ferrous metals). A
commercial brand is sold by welding supply stores for pickling steel
however, the commercial steel pickles are quite caustic and require
a porcelain pot (never metal alloys in any part of their
construction) or a lead pickle pot (which has its own hazards in
handling)- also very good ventilation is a must. You can always clean
stainless without pickle if not soldering it - for instance using
wire and making jump rings requires only deburring for which you can
use a pumice wheel or shaped point of your choice in a flexshaft or
micromotor…rer

I. concaved the strip then formed it around my bangle mandrel. 

Don’t you need to hammer it on the mandrel and doesn’t that
de-concave it (in a non-uniform manner)? Janet in Jerusalem

Don't you need to hammer it on the mandrel and doesn't that
de-concave it (in a non-uniform manner)? 

I dont use a steel hammer to do this, I use a rawhide one or a
medium plastic or even a soft wooden mallet. anything that doesnt
mark the metal, cos I polish it before bending. Easier!!.

Also it does tend to flatten the concaving, but when its to the
bangle (open cuff type) shape, then mallet it down on its side to
raise the edges…

What your doing is stretching the outside edge.

Done hundreds of them in every metal (except gold).

The other trickier one is doming the middle of the metal, especially
when the edges are rolled into a small tube section.

Done it in 30/1000in titanium.

gorgeous when polished and fire oxidised a mallard green with ring
and necklace to match.

Ted.

Form the inlay as though it was a sheet of metal first, then design
it : Use your forming tools to make the bracelet shape and solder it
closed ( for a bangle), leave it open ended if you are going to make
a clasp closure, then dap it to concave/convex, next forge any
finishing touches. Remember when making bangles- a variety of sizes
is appropriate if selling to a mixed audience that aren’t all twenty
somethings with small wrists. rer