I am planning to make a ring out of two pieces of 0.75mm
14K gold sheet. The first sheet will be cut to about 7mm wide by
whatever length the ring size requires (say 60 mm) and will be
pierced with an intricate design. The second sheet will be cut to
the same size and will be sweat soldered to the first. so that I
will have a 7mm wide by 1.5mm thick by about 60 mm long piece.
Milt, you'll have a harder time doing this with the gold than with
sterling. The main problem is that the pierced outer layer will wish
to stretch around the inner piece much more than you may wish, as it
may well distort the pattern. If you can tolerate this distortion,
then your main problem will be the seam.
In general, don't bend the ring to a simple round shape and expect
the seam to square up. in the main portion of the band while you
bend it, the inner layer compresses a bit, and the outer layer
stretches. At the ends, neither of these happens, and the result is
too long an inner surface and too short an outer one, so the seam
ends up V shaped. the usual practice in such a situation would be to
leave a slight bit of extra length to the blank (so the short outer
layer is still long enough. then saw through the closed up seam,
perhaps several times, each time closing the seam again, till the
sided have been matched up. If you've got a lot to remove, you
might try a seperating disc for the first cut.
the other method, and one I prefer in many cases, may not always be
appropriate since it requires an even tighter bend in two places,
just in from both ends. whther this will work depends on the delicacy
of the pierced work at those areas. The idea is to bend your blank
by first bending the ends up at almost a 90 degree angle (soft curved
bends, still) Now bend the area between the two bends to complete
the closed figure. But it will give you a sort of D shaped ring, not
a round one. What this does is to keep the ends of the blank flat,
so they don't distort, and you line up the ends in a straight
line/flat plane. this allows previously carefully cut ends to be
lined up. After the seam is soldered, you then put the D shaped ring
on a mandrel and use a mallet to round it out.
However, it may also be that you'll find the lengthwise stretching
and distortion of the pierced layer when you bend your laminated
blank to be unacceptable. In this case, make the solid band the
right length to form the ring size you wish, and bend it around to a
ring, solder it and finish the outside surface to a smooth ripple
free surface. Then the pierced band is left a bit longer, (the
actual amount longer, for .75 mm sheet, will be about 2.3mm longer).
that will give an outer band that, once bent around, should just
slip over the inner one snuggly.
You then solder the two together AFTER they've been bend around into
telescoping bands.The soldering can be trickier, and you must take
care to get the two bands to fit snuggly together. but you'll have a
lot less distortion of your pierced pattern this way.
In bending heavier stock, you may find that rather than ring
benders, which can be pretty brutal, it may be more effective to use
a groove in a hardwood block. the groove is either half round the
size you wish, or better, a V groove. You place the blank over the
groove, and a ring mandrel in the middle centered over the space
underneat the blank, and use a mallet on the mandrel, not the blank,
to forch the blank into the groove, forming it around the mandrel.
This avoids tool marks on the blank. And you can get a lot more
bending force with an impact from a hammer or mallet on your mandrel,
than with most pliers.