Making a two piece ring

      First, I found the 1.5 mm metal very hard to work with.  I
bent it with ring pliers and used a ring mandrel and rawhide mallet
etc. Once I got the ring to close, I discovered that the two ends
were not perfectly square to each other.  I had a real hard time
squaring the two 1.5 mm x 7mm surfaces to match with no gap.  This
surface is much larger that the typical ring that I have made our
of 18 ga sterling in the past.  Also I annealed the ring several
times while trying to form it When I have made this type of ring in
the past,  

I have made this type of ring several times in the past. After
piercing the outer piece of the ring I would form rings of each
piece and solder each of the joints allowing for the extra diameter
for the outer piece. I would then put one inside the other and make
a tight fit by tightening a little from the inside with a wedding
band expansion sizer. When forming the inside ring I sometimes have
to cut and resolder it several times to get it around slightly
smaller than the final ring finger size. I find if I use hard solder
and anneal, I can expand the inner ring a small amount without
breaking the solder joint. Stagger the solder joints of the inner
and outer rings and you will have a much stronger product. I then
sweat solder into the joint between the two rings starting at a
point in between the solder joints that join each ring together.
Sometimes I use the compression dies of the wedding band sizer to
close the outer ring onto the inner ring (slightly). Don’t try this
with a pierced outer ring though, the high stress will deform the
ring where the piercings have weakened the cross section of the
ring. If you insist on soldering the pieces together before forming
the ring, I find that the easiest way to true the ends when they
come together is to press the two sides together while passing a saw
through the joint. You’ll have to do this a few times, each pass
removing a small amount of metal and bringing the two sides

Robert Hood