As a first approximation, the internal diameter of each ring is
equal to the internal diameter of the required ring, plus the
thickness of the metal used.
A size 8 has an internal diameter of 0.71". If the thickness of the
metal is.07" (you can figure the gauge - I use real measurements)
then the internal diam eter of each ring is 0.71+.07 = 0.78", which
is about size 10. Because the internal shape of a rolling ring on the
finger is a rounded triangle rather than a circle, and because they
don’t really slide on and off the finger, you can afford to make
them a little smaller than you would for a solid ring of similar
Link the second ring on the first one, and the third one through
both. You can’t do it wrong.
You will need a ring mandrel with a groove in order to make each
ring round after soldering, and, with care, it’s possible enlarge
each ring a little with a roller-type ring stretcher.
Regards, Gary Wooding