Oh great! I run into students who want to do something like your
project as a first project all the time. Not long ago, I even had one
student (with no background in metals, clay, or any kind of art) who
insisted on trying to do her very first project out of gold clay! I
hate to discourage budding artists, but they are never satisfied with
what they make on a first try when they start with such high
expectations. Pardon me if I came off too strong in my earlier email.
Pam’s suggestion of using the photopolymer plates is the best
approach to your mold problem. Just be aware that you may have to
make several before getting it perfect.
Do look into the metalclayfindings ring liners as Pam suggested. Or
make your own using sheet/wire. You also might be interested in the
ring shank molds now being offered by several of the metal clay
companies. These molds make a seamless ring blank that is solid and
When you make a metal clay ring by wrapping it around a mandrel,
finishing the interior to be smooth can be very time consuming. If
you choose this method, you can use the following directions to join
Always be sure to wrap the ring mandrel with freezer paper, teflon,
or some other kind of release paper. Don’t build a ring directly on
the mandrel as it will shrink as it dries and get stuck. Wide rings
should be made on a stepped mandrel rather than a tapered mandrel.
Most metal mandrels are made of aluminum or carbon steel and you
never want to leave wet clay on these. The aluminum reacts with the
silver and will give you a poor result (see
for details). Carbon steel will rust, leaving a stain on both the
mandrel and the silver clay.
To join the ends of the clay, wrap the clay tightly around your ring
mandrel and overlap the ends and cut on a diagonal, remove the excess
clay, place (not join!) the ends together and dry until the clay is
leather hard. A diagonal will spread the stresses on the clay and
give you a stronger join than a vertical cut. As it drys, the clay
will shrink a little, and you may need to shift the band to a smaller
mandrel. Now you can join the ends using paste and pressure without
deforming the band. Allow to dry and add clay/paste/syringe as
desired for fine finishing.
Silver clay rings are generally made anywhere from 1.5 to 3 ring
sizes larger than the desired end result. If you do a lot of sanding
on the inside of the ring, you effectively increase the size of the
ring, so you might want to start at the lower end. If you are not
going to remove clay from the interior of the ring at all and intend
to fire at 1650F for 1-2 hours (to get the strongest ring possible),
you will find that it shrinks almost exactly 3 full ring sizes (US
sizes). Fire the ring around a ring insert made of jeweler’s
investment that is the size you want the ring to end up as.
Ring inserts can be purchased from a number of silver clay vendors
or you can make your own. Several vendors sell molds for making your
own inserts. You can also make your own by wrapping freezer paper or
teflon around a stepped mandrel, taping it and using the resulting
tube as a mold in which to pour investment. Be warned that making
your own this way is trickier than it sounds as you often end up
with ovals instead of rounds, air bubbles/gaps in the pieces, and the
process is pretty messy. Be sure to use a jeweler’s investment for
the most accurate results even though you may hear claims that
regular plaster will work. Some plasters may work, but many plasters
shrink when heated.
As for stone setting in a ring, it is the same process as setting in
a flat piece, but needs to be done after the ring is wrapped around
the mandrel. If you try to place them (with dents or holes) on the
flat, the warping when you curve it may be a problem. Exactly how
you do it will depend on the method you intend to use for setting the
stones. You can make dents in the clay (with a tool or by pressing
the stones into the clay), cut or drill holes after the clay is dry.
For the most precision look, you will want to drill holes after the
clay is dry. Use a pin vise and a small drill bit to get started. If
you want a flush setting and your stones are round, use a setting
bur that matches the size of the stone or is 10% larger. Obviously,
the clay will need to be thick enough to accommodate the stones you
Does that cover all the questions raised?
Mary Ellin D’Agostino, PhD
Sr. Teacher, PMC Connection
Certified Artisan, PMC Guild