Ring sizing mandrel for non-round rings?

Does anyone know if there is a product on the market for sizing non-
round rings? I have a grooved mandrel which helps (somewhat) for
sizing some U-shaped rings. But what I’m really looking for is
something made from a firm but flexible material (like silicone?)
that will slightly conform to the inside of an unusual shaped ring
(like a finger would) for a more accurate size measurement.

Thanks for your help!
Danielle Miller-Gilliam

I have a grooved mandrel which helps (somewhat) for sizing some
U-shaped rings. But what I'm really looking for is something made
from a firm but flexible material (like silicone?) that will
slightly conform to the inside of an unusual shaped ring (like a
finger would) for a more accurate size measurement. 

I actually have such a mandrel, made of a black rubber. Commercially
made, but it was given to me by another craftsman, so I don’t know
where to get one or if they’re still made. However, it’s not all that
accurate, since the rubber is somewhat compressable (the mandrel is a
hollow tapered rubber tube, making it a bit flexible), so the size
you measure depends some on how hard you pull the ring onto the
mandrel. Still, it helps, if you couple it with comparisons to a
standard ring sizer pulled similarly hard onto the mandrel.

Then there’s the classic do-it-yourself model. Take a sheet of
ordinary typing/computer paper, and wrap it tightly around a standard
steel mandrel, taping the outer seam shut with scotch tape or the
like. Remove from the steel, and insert it into standard ring sizers
in order to use a pen to mark the sizes on the paper. This works
reasonably well, and when it gets raggedy, is easy enough to make
another. Like my rubber mandrel, us it in comparison to how a
similarly marked standard sizing ring fits the paper mandrel, versus
your ring to be sized, since the paper too, flexes and gives a
little, so how hard you pull the ring onto the mandrel makes a
difference.

And finally, measure your various knuckles to find one that fits the
ring in a somewhat similarly feeling fit to some known standard
sizer. This, in my experience, may be the best method to get the most
accurate size, as it compares how the ring feels on an actual finger,
regardless of how distorted the shape may be, the comparison will
tell you what the ring should be stated as measuring.

Peter

Danielle,

I make lots of different shaped rings in my studio, on one of 4
"other than round" mandrils I have. None of these squarish mandrils
I use have size markings on them, which would be nice, but I’ve never
seen one with this feature. The problem is that with square rings,
there is an air space at each corner, so it doesn’t fit the finger
the way a round ring would.

I am contemplating taking a few sets of metal ring sizers, and
forming each ring sizer set on each mandril I have. So each mandril
shape will have it’s own sizer in that same shape. That would seem
to me to be the most “bulletproof” way to assure the match of the
sizer to the specific ring mandril shape. A lot of work to alter each
sizer set, but then you’ve got the definitive size for your specific
mandril shape. The sizer sets are not very expensive, and when I
find the time, that’s what I’m going to do.

Jay Whaley

Hi Danielle,

Does anyone know if there is a product on the market for sizing
non- round rings? I have a grooved mandrel which helps (somewhat)
for sizing some U-shaped rings. But what I'm really looking for is
something made from a firm but flexible material (like silicone?)
that will slightly conform to the inside of an unusual shaped ring
(like a finger would) for a more accurate size measurement. 

One method of measuring a non-round ring is to place a strip of
paper (one that is as thin as possible and no wider than the ring)
inside the ring your measuring and carefully mark it where the two
ends meet. Tape it together at the mark and place this paper ring on
a round mandrel. The size you get will be slightly smaller than the
actual size of the ring…how much smaller? That depends on the
thickness of the paper and how closely the paper conforms to the
inside of the ring. Measure the clients finger with a normal round
finger gauge and compare the two sizes to see how much larger or
smaller to make the ring.

Larry
Cary, NC

Danielle- You can buy flexible ring mandrels or make your own. We
cut apart a brown paper bag and then roll it onto a metal ring
mandrel. We glue the paper to itself with carpenters glue. Trim the
edges and and tuck the ends into the inside for a nice rolled edge
that helps strengthen it. Then mark the sizes with a black permanent
marker. After that take it outside and spray it with clear spray
paint. Repeat the spray after it dries. This will make an almost free
flexible ring mandrel. Mine last for many many years. Have fun and
make lots of jewelry.

Jo Haemer
www.timothywgreen.com

ps: The slotted mandrels are used for sizing rings that have stone
culets poking through the bottom of the ring.

Hi Danielle;

One used to be able to buy exactly that, but whoever used to make
them doesn’t anymore. I wish I’d bought one when they were still
available. I anyone knows where to get one of these, I want to know
too.

David L. Huffman

I use my fingers. I try a ring guage of the correct size on a
finger, make a mark on the finger, then fit the ring to that mark.

Non-round rings are free-form so final adjustments in size are
hammered up in appropriate places on appropriate mandrels (it really
helps to get the size right the first time), and final profiles are
corrected by careful bending with pliers or by whatever means are
necessary.

Alastair

Peter, I have one of those mandrels which I purchased from Rio years
ago. I don’t know if they currently carry them. It works well when
it’s called for. I’ve found that it reads one half size off. So,
with that adjustment it’s fine.

The problem is that with square rings, there is an air space at
each corner, so it doesn't fit the finger the way a round ring
would. 

Well, Jay, I’m looking at my fingers, and they’re really pretty
squarish, down close to the knuckle. I’ve never seen air space when
wearing a squared ring, and in fact feel that they fit better than
round, though fingers seem to fit themselves into many ring shapes
without problem.

In any case, I like your idea of re-working sizers to fit squared
mandrels. Then, as far as I can see, you’d have to assign sizes by
comparing the fit on actual fingers, using standard round sizers.
Find a finger that is size 8, find the square size that fits that
finger, etc. PITA, but it would work.

Noel

I wish I'd bought one when they were still available. I anyone
knows where to get one of these, I want to know too. 

Ditto, David. Jo-Ann has a rubber ring mandrel (she’s not sure if
Kevin Kelly gave it to her). One of our retail clients came in and
saw and “pretended” to steal it. “If you ever find a source for
them, I’ll buy 10!” I surfed all the usual suspects, nada…

Dear Jay,

Don’t just contemplate reshaping the ring sizers, go ahead & do it.
We altered 2 sets already- one for the studio and one set that we
take to shows. It’s called “Hello Arthritis”… (Aside from the
artistry of square rings) There’s about a 1/4 size differential
between a round ring size and the squared ring mandrels. Makes it
MUCH easier for swollen knuckles to deal with rings and better
craftsmanship than putting in sizing balls which some people still
do. Our customers love the new to them shank shape. Just slide them
on the diagonal on your finger, points up and out, and then swivel
into position once past the knuckle. They won’t slide around on the
finger, they will stay straight up and balanced. My husband started
shaping all his rings that way as he got tired of losing rings that
could fit over his knuckles but were loose once on. Another bonus
besides arthritis…No more finger pinches when grabbing a heavy bag
or laptop. And they are aesthetically pleasing to look at too. Cool
modern look.

Ruthie Cohen

Concerning the soft mandrel, for years I have been wrapping a single
sheet of paper tightly around the mandrel then tape it shut. Then
using my ring sizers, slide each one up tightly on the paper, mark
lightly with a pencil on each side of them until you do all
corrosponding sizes then mark the center of each one in pen with a
line and size number. Slide off the mandrel there you go! Lasts for
quite a while. On a side note just before the foam one came about
25 /30 years ago I had the idea ($15- 20,000.00 tooling set up for
the mold) and I guess someone in Texas beat me to the punch.