Bezel setting a brilliant cut stone

i am trying to recreate a ring i made several years ago when i was
first learning to set stones.

ironically, my persistence then led to something which seems now to
be unrecreatable.

despite the fact that my skills are improved.

i’m trying to set a brilliant cut topaz in a similarly shaped
bezel… i.e. in a funnel shaped piece of silver. the challenge
arises
because once at the top of the stone, the bezel angles outwards at 28
degrees, rather than inwards, and is not totally perfect, so the
challenge of rounding it over the edge is damn near impossible.

how did i do this before???

does anyone know any hints or tricks?

i attempted fashioning another piece to solder onto the top which
was donut like but coned so that the inner diameter allowed the stone
to fall through but once hammered would keep it set, but it’s quite
tricky.

i could and will try that again, but there must be a way!

suggestions very welcome! thanks to all -
hilary

Have you tried cutting a seat or bearing for the girdle of the stone
to sit it?

it’s a huge stone – 18mm – so the idea was to make some kind of
crazy bezel that would totally fit to the stone. i’ve done this a
number of times with for example emerald cuts. just a lot of
highschool geometry, working with disk separators, angling,
protractors, etc. but it works. but this… i mean i guess i could
get a piece of 8mm sheet, a bowl of water, and a huge setting bur,
and attempt to cut the seat… admittedly, at least that would work!
but i guess the friction has just turned me off. and yet i really
hate prongs so… there must be another way! maybe if i made the
bezel and the soldered on a piece of 1-2 mm sheet for the top and
cut the girdle in that?? thanks for all your thoughts and ideas - i
really appreciate it!

it's a huge stone -- 18mm -- so the idea was to make some kind of
crazy bezel that would totally fit to the stone. 

I’m not sure I understand correctly, but I think you’re saying you
want to set the stone into an inverted cone that is the same taper as
the stone? But you can’t just bring all that metal in at the top to
fold over the stone?

If that is correct, I think what I would do is construct the cone
out of suitable sterling, and cut/file/sand the top so it just
reaches past the girdle of the stone. Then I would make a fine silver
(or 22k gold?) bezel of just enough height to hold the stone and
solder it to the cone. Easiest, probably, if you make it just a
little too small and stretch it up by rolling on a bezel or ring
mandrel on a steel block. This will work harden it and keep it round
while you position it carefully, then of course soldering will
anneal.

This should fold in easily, and you’ll have a nice, crisp angle on
the top of the setting where the girdle sits.

Did I understand right?

Noel

Did I understand right? 

You understood exactly! Thanks so much. I will give that a try. I’d
been toying around with that idea, but didn’t know to do the bezel
ring out of fine silver. Many thanks for the help!

it's a huge stone -- 18mm -- so the idea was to make some kind of
crazy bezel that would totally fit to the stone. 

How about making the cone as you describe, but trim down what would
otherwise be the entire bezel into many prongs? That would provide a
sturdy hold, and the metal would work over the edge easier than an
uninterrupted bezel.

Lorraine

How about making a mandrel the same size as the stone mounted on a
rod that could be used to carefully hammer the metal to fit the
bezel, stop just when it’s ready to fit the stone. You wouldn’t have
to have it match the stone precisely, only in primary dimensions such
as the girdle diameter, culet to girdle height, and the pavilion
angle.

Mike DeBurgh, GJG
Henderson, NV

This may not help you, and I may not be visualizing your bezel quite
right, but I would typically cast a bezel like that. First of all,
please forgive me if this is explaining something you already know.

If you have a lathe you can turn it to get it as close as can, then
carve the rest. Or if no lathe or mill is available, carve a wax.

I would cut a piece off of a wax ring tube (flat top) as wide as the
wide st point of the bezel you need and ream it out to the correct
finger size to get the right curvature at the base of the bezel. All
you need this wax for is the bezel so you don’t care about the rest
of the shank, it just makes it easier to hold on to.

-Mark the height of the bezel with a scribe and trim the wax to
height.

-Mark the center of the top flat with intersecting scribed lines.

-Drill a hole at the center of the flat top where the lines
intersect. (You need to work from the inside out on bezels, really on
almost everything)

-Use a cone bur or bud bur to remove almost enough material that
your 18 mm stone will nearly fall in the hole (hole should be under
18 mm at the top edge).

-Take a setting bur that’s a hair under the diameter of your stone
and cut a seat that is at the desired depth.

-Lay your stone over the hole and put your wax pen on the table,
Heat the stone (pen should not be glowing red) until it melts into
the seat and rests at the desired depth.

-Let it cool a little bit and push the stone out from the underside
with a toothpick. You now have a perfect seat for your stone.

-Trim the inside of the bezel at the seat with a ball bur so you
don’t have an excessively large seat touching the pavilion. If you
don’t do this it will goof you up when you go it set it. You really
want a minimal seat, enough to hold it but not too much too much to
push the stone out of position.

-Make sure the rest of the inside of the bezel is just how you want
it, the hole at the base is centered and the right size, the walls
taper evenly, etc.

-Now that the inside of the bezel is all ready you can begin to file
and shape the outside of the bezel so it looks just how you want it
to.

-When it’s ready you just cut it off the shank and cast it.

-After you finish it and solder it in place, setting it is much
easier because you already created the seat for the particular
stone. It won’t fit right in the seat because of a little shrinkage
and because the bezel will no longer flex.

  • If it were me setting it I would probably trim the opening just a
    bit with the vertical edge of a setting bur to make it so the stone
    just almost fits in the opening and so the inside edge of the bezel
    is perfectly round.

-I’d then clean up the seat with a 70 or 90 degree hart bur
(depending on the angles of the stone).

-If needed I’d lift a portion of the bezel lip a hair by running the
tip of a round nose pliers around the inside of the seat, just enough
to lay the stone in place.

-If seated properly I’d then knock down the bezel with a hammer
handpiece.

This has to be done carefully and would take another few paragraphs
to explain…so if you’re not accustomed to that tool use a burnisher
or whatever you’re comfortable with. If you are using a hammer
handpiece it’s as important to shape the bezel as it is to tighten
the stone.

Sorry this was so long. It is so much harder to write this stuff down
that to just show someone how to do it. Anyway, hope it helps.

Mark

This may not help you, and I may not be visualizing your bezel
quite right, but I would typically cast a bezel like that. First of
all, please forgive me if this is explaining something you already
know. [snip] 

Wow!!

What an amazing tutorial!

I’ve never contemplated making a bezel out of wax first due to the
shrinkage issues but you have certainly inspired me to give it a
shot - Thanks a million!

I did finally manage to set that particular stone by hand doing a
sort of double bezel, but it’s still not “perfect” which is ok, it’s
still beautiful, but it also makes me want to give it another go. So
your method is next on the list:)