Setting square cabs

Hi,

I am having trouble finding about setting square cabs.
There are lots of articles about round and oval settings but nothing
about squares and odd shapes. It’s the corners that I need help on,
naturally.

Thanks.
Rockey

Hi Rockey.

I am having trouble finding about setting square cabs.
There are lots of articles about round and oval settings but
nothing about squares and odd shapes. It's the corners that I need
help on, naturally. 

It sounds like you’ve had some bezel experience so maybe just a few
tips on corners are what you’re looking for. You can do it with some
practice and a little confidence.

Make sure that the height of the bezel is appropriate for the stone.
Depending on the slope of the stone, you may need to file down the
bezel a little bit toward the corners. To fit the corner really well,
file a “v” shape (mitered corner) in the bezel right at the corner so
that the notch comes down a little on the shoulder of the cab. This
eliminates the buckled bezel blues.

With practice you’ll get the angle just right. After rolling the
bezel in place, touch up the surface of the notch with a fine file or
emery. Then burnish the bezel well and when you polish the metal you
can’t tell there was a split.

For some other tips about working with odd shaped bezels, check out
my article “Bezels for Irregular Stones” in February 2000 Lapidary
Journal.

Pam Chott
www.songofthephoenix.com

rockey -

It's the corners that I need help on 

square cab bezels are pretty much the same as round/oval bezels.
some jewelers use the ‘L’ procedure with two pieces of bezel bent
90%, one side of each has to be the width or length of one side of
stone and the other side longer. these 2 ‘L’ pieces are put together
to form a square in which the cab will fit snugly and then the two
corners are soldered. it works okay but leaves you with the two
soldered corners sharper than the 90% bent corners.

i just bend the bezel strip (26g is best for me, doesn’t melt with
harder solder) around the cab so the solder seam falls in the middle
of the bottom side - that way all the corners are the same. since i
usually make the bezel width a little higher than the stone, when i
dry fit it to snug it up i overlap the two ends and clamp with a
locking hemostat, then saw along one side of the hemostat - the edge
seam matches up better.

if the bezel is a little higher than you need, mark the desired
width around with small dividers, and sand down on a 220 grit disc.

ive
who knows that finding your own successful way of doing things gives
you more time to do other things - your way, of course.

Rockey,

It's the corners that I need help on, naturally. 

As with any square stone (or anything with a point/corner), faceted
or cab, best to remove any metal which would come into direct contact
with the corners. The corners have the highest potential for
breakage, so avoiding direct pressure is essential.

For a cab, if the bezel is heavy enough that you have to hammer-set
the stone, use a small round or inverted-cone bur (1mm) and cut a
“trench” out of the corner, stopping just below the top of the bezel,
such that when the stone is inserted, no contact is made at the
corner. By doing this, when you actually punch the metal down over
the stone, no pressure is directly applied to the corner, even when
you are moving metal at the corner.

For a thin bezel, which may be rolled over using a burnisher, file
over the top edge of the bezel a hair at the corners, rounding them
off slightly. This will help eliminate any crimping of the bezel when
it is pushed over, as there will be less metal trying to occupy the
same physical space. Play with the amount to be filed off as
heights/radii change from stone to stone, so you’ll have a feel for
what works best with different profiles.

Matthew Crawford
www.MatthewDesigns.com

Rockey;

If you permit me, I will write an article just for you, on how these
little ornery stones can be set with little difficulty. I will try
and identify any problems once we have certain holydays behind ‘us’.
This writer also needs some time off,…:>)

You did propose a very interesting article / essay for my four “Bench
Conference” seminars starting April 27-30th in Denver, CO. Let me
just let you know that this essay will be written, for sure, and I
won’t let you down…Gerry Lewy!

You don’t say much about what your difficulties are in setting, but
I imagine they are the usual. That is - set the corners first. If you
do the obvious, setting the walls first, the corners will always
pinch in that way they do, and you will never get them back. Always
set the corners first…

I completely agree with John Donivan who said:

 ... set the corners first. If you do the obvious, setting the
walls first, the corners will always pinch in that way they do, and
you will never get them back. Always set the corners first. 

But I would add that this becomes a lot easier when you are using a
softer metal like 22k (or pure silver). As you work each corner, the
metal will compress until the gaps eventually disappear. Then you can
move on to pushing in the bezel sides. For this method to work, the
bezel cannot be significantly higher than the stone. There should
be just enough height to end up with a slightly less than 90 degree
in-curve at the corners. Notching the corners, as others have
suggested, will also work but IMO the end result is cleaner when you
don’t.

Sometimes, when the corners of the stone angle up sharply – which
makes the task much trickier – I will use a fine diamond tool on the
flex shaft to remove the sharp corner points of the stone. Since the
corners will be covered by the bezel, this is never visible. Most of
the corners you’ll see at the URL below are more acute than the 90%
you get with a square, yet nothing was notched.

http://www.bethrosengard.com/Collections/ArchivesPopups/FernwoodEars.html

Hope this helps.
Beth

Hello members on Orchid !

Here is MY version on “How To Set a Four Cornered Stone”. Lets put
away all of the lessons about the Princess Diamonds and their method
of setting. This method you will learn is totally different. This is
almost like a Four-Sided, bezel. It’s just that plain and simple.
What tools do you need to have at your bench? Not too mention their
variations, well here they are.

Pillar file #1 cut
Pillar file #2 cut
Round burs of ranges from #006 - #010
Pumice wheels of #180 grit, Flat edge and ‘Tapered Point’ edge.
Secure ring-holding device of YOUR choosing.
Metal pushing tool, preferably not copper…(too soft)

Do not use any Hand-Held, or Reciprocating Hammer! Metal pushing
device should have a serrated edge, on its pushing ‘face’.

First of all make very sure the stone in question is not
overpowering the bezel walls. WE do not wish to alter the bezel in
any way shape of form. This stone must almost sit inside the bezel
walls. Prior to letting the stone be placed inside and sometimes they
will get stuck inside and cause you much grief. Examine with your
10x power loupe at times. Examine that all of the internal setting
areas are totally free of any casting irregularities, bubbles, extra
shards of gold, or any defects caused by the casting process. This is
more than important, this allows no adverse setting problems, or loss
of the stone due to breaking or chipping.

I would ask you to now to use a randomly selected round bur and
remove any extra gold that does is not needed. These pieces can occur
right at the bezel base or at the junction of the wall. Let your bur
run fast and this way it will almost polish as it’s drilling. I would
also run a bur along the base of the wall at the same time.

Please examine the stone in question, do YOU feel that the stone is
going to meet at the corners of the bezel? If not, YOU should adjust
the bezel wall…not the final shape of the stone. Both the stone and
gold must meet at the same location, just prior to tightening. Here
comes the easy part, with your Pillar file #1 (rougher cut) thin out
the very top of the bezel wall. This must be only at the very top,
why? Glad you asked, so ‘we’ the setter won’t be pushing too hard as
to damage the with undo pressure and break the stone. I normally file
at a 45degree angle on the outside bezel wall tip. I want to press
over with just enough pressure as to not to break the stone. Now
comes the very important area of this whole process. The Four
corners.

Once you have ascertained that the stone can be placed INTO the
bezel. Allow some time as to see just exactly where the corners will
meet, it is at this axis or section at eh bezel is just where you
must now drill a hole. This hole will prevent any touching of the
stone to the bezel wall. I call this the “Floating Corners”. NO METAL
MUST COME IN CONTACT AT ANY TIME DURING, OR AFTER SETTING. Let me
just say that it is the sides of the bezel wall that is 'holding
’the stone.

Have you done your homework and judged for yourself how the bezel
wall and the base is cleaned. WE do not want any undo breakage of
this stone once the pressure is being put against the stone while
setting. I would at this point allow a smaller round bur and create a
side or oval opening of the four corners. This will allow some wider
distribution of the girdle mass of the stone and along the
bezel…I will now request that you use a #008 round bur and create
a bearing cut, or groove to allow if the stone has a slight girdle.
We are not speaking of a Cabochon in this case, but a faceted stone,
I presume!.

To identify a ‘well prepared’ stone setting, please make sure if the
four corners are matching against the bezel walls. Are your newly
made bearing cuts in line and not deviating from the symmetry of the
girdle? If this is accurately accomplished, I would now place the
stone in the bezel. Hoping that the stone is not ‘rocking’…this is
due to an absence of the cleaning care with your round burs during
the preparation process. With this “hand-pushing” you can easily even
set an Opal, baring any internal inclusions.

Place your stone in the bezel, Now with your metal pusher, not the
hammer at this point. Start to press the filed metal right beside the
actual corner, NOT AT THE CORNER at this moment. We are now pressing
over a total of “8 contacts”, not just four.

These two “contacts” are just on each side of the bezel corner, got
this so far? You will have little difficulty with the metal being
shaved off at a 45degree angle. Your pushing tool must be rocking
over the metal towards the stone. Do not let the metal pusher
actually TOUCH the stone. With any bezel, make sure all the gold is
over and touching the facets of the stone.

Now once the stone is being totally tightened all around the 4
sides, GENTLY and with great care, lightly press, or mold over the
actual corner and let the gold “sit against” the stone. But with
extreme care not to push hard over the stone, trust me, you will have
great anxiety if the stone breaks. Those strange words cannot be
mentioned on Orchid…:>)

Once the stone is now set and secured, use your finer cut, Pillar
file #2 cut and file to smooth-over the gold and remove most of the
"pushing marks". Use a file against your finger pad, try not to let
your file touch the stone. Another way to damage the stone too. Once
most of the marks have been removed, use now your Flat edged Pumice
wheel with a #180 grit, and smooth the surface. There should me no
marks at this point to look at. With your Tapered, Pumice wheel just
do a ‘touch-up’ on any indentations surrounding the setting.

Remember, the FOUR corners are to be used only as an illusion, the
maximum holding is done by basically the FOUR walls.

Hope that this has been a help to all. Also remember this is my
perspective on “How set a Four-Cornered Stone”. This can be used as
an ‘alternative’ stone technique…

Gerry Lewy!

But I would add that this becomes a lot easier when you are using
a softer metal like 22k (or pure silver). As you work each corner,
the metal will compress until the gaps eventually disappear. Then
you can move on to pushing in the bezel sides. For this method to
work, the bezel *cannot* be significantly higher than the stone.
There should be just enough height to end up with a slightly less
than 90 degree in-curve at the corners.

Absolutely!

The first step in bezel-setting a cab with sharp or acute corners is
to begin with a cab which is properly cut. I see many on sale
commercially with sharp angles AND with no shoulder to speak of, but
rather a dome which seems to continue all the way to the base of the
cab. They look like you could prick your finger on 'em and draw
blood.

A well-cut cab should have a shoulder all around which is cut a bit
shy of 90 degrees, and which is slightly less tall than the bezel
wire which is to be used. If you follow this formula, and follow the
practice of starting with the corners and working out, you can have
nice, well set, sharp-cornered cabs every time. If you start with a
cab with a wicked sharp pointy part, and the dome extending all the
way to the base of the cab, setting the stone cleanly will be
problematic.

Lee

Hi Beth.

...For this method to work, the bezel *cannot* be significantly
higher than the stone. There should be just enough height to end up
with a slightly less than 90 degree in-curve at the corners. 

A stone such as your example - with a bevel and “buff top” - is
ideal for setting as you have described. I love stones cut this way!

... Notching the corners, as others have suggested, will also work
but IMO the end result is cleaner when you don't. 

I completely agree with this comment. However, many times the
contour of a cabochon is curved from the dome to near the bottom. On
a square - or any cornered cab - this presents a dilemma in that the
proper bezel height for the sides is far too high for the lower
corners.

In this situation, a compromise in bezel height must be made to
effectively and aesthetically secure the stone.

...Most of the corners you'll see at the URL below are more acute
than the 90% you get with a square, yet nothing was notched. 

Stunning earrings, Beth and beautiful workmanship!

Pam Chott
www.songofthephoenix.com

there is a old saying; “measure twice, cut once.” If that doesn’t
apply to just about anything we do, I don’t know what does!

Square bezels would be easy (I’ll get to the way I did it in a min)
if a person took the time to get the size right, then marked the
corners, get it to the right height, and so on. Then there isn’t
much in the way of “making” the bezel the right size the hard way.
(which is when it’s already soldered together)

My experience was this…

I got this great stone a few weeks ago, and one night I finally
settled on a design. (I’ll have pics of it later) well this stone was
odd shaped, no real flat surface on the bottom, and the design called
for a element to go over the top of the stone.

All this meant a few things to me. The first was I couldn’t really
solder the bezel onto some flat stock and go from there. I had to
make a band that went around the whole stone, with the top element
holding it down in the mean time. It also meant I was setting both
sides of the stone at the same time, and fighting to keep it
somewhat even in the bezel.

Well, it was getting late and I almost gave up a few times, but I
did get the top set pretty well. You can see lines on the edges, but
they “aren’t too bad.” I also got the bottom down pretty well, not
as good as the top, but it does it’s job.

I took a file to the corners, and found out it really works well,
however I learned that I took a little too much off. It would have
really worked if I did a little at a time. A channel in the corner
would have worked well too, but I didn’t have a burr that small
handy.

it was also at night after my “real” job… and I was doing it “by
the seat of my pants” and not taking the time to measure things out
and set it up correctly. Not that the seat of your pants isn’t fun,
but sometimes a person just needs to take a few steps back and “take
the time” to do things right, research, and ask questions.

I got though it, but it could have went a lot better if I would have
done some homework. However, my friends and family like the piece,
so it did pass the test!

Andy
mpls mn
www.andrewthomasdesigns.com

Hi Pam,

However, many times the contour of a cabochon is curved from the
dome to near the bottom. On a square - or any cornered cab - this
presents a dilemma in that the proper bezel height for the sides is
far too high for the lower corners. 

Yes, absolutely. It is with a stone like this that I round off the
corners with diamond tools on the flex shaft; but I understand that
not everyone would find this practice acceptable.

In this situation, a compromise in bezel height must be made to
effectively and aesthetically secure the stone. 

Agreed, again. I should have added in my original post that I do,
when necessary, trim bezel height. (This is necessary also with
stones whose shoulder/sides are uneven, like many drusies.) But I
don’t notch; I taper.

Stunning earrings, Beth and beautiful workmanship! 

Thanks, Pam! Much appreciated.

Beth

I agree that a well cut square stone and having it at the right
height in the bezel is key to setting it. When I set a square stone
I will often first go over the corners of the bezel with a fine wheel
(like a Pink High Shine) on my foredom, just to thin it out ever so
slightly, making it easier to push down onto the corners of the
stone - but always, always get the corners down first.

I am having trouble finding about setting square cabs.
There are lots of articles about round and oval settings but
nothing about square and odd shapes. It's the corners that I need
help on, naturally".

I simply forgot to send this article/essay out to Cyber-Setting Land
last month. Because of the past “Bench” conference it slipped my
mind. Here it is, a bit late, but not forgotten…

Here is MY version on “How To Set a Four Cornered Stone”. Lets put
away all of the lessons about the Princess Diamonds and their method
of setting. This method you will learn is totally different. This is
almost like a Four-Sided, bezel. It’s just that plain and simple.
What tools do you need to have at your bench? Not too mention their
variations, well here they are.

Pillar file #1 cut
Pillar file #2 cut
Round burs of ranges from #006 - #010
Pumice wheels of #180 grit, Flat edge and ‘Tapered Point’ edge.
Secure ring-holding device of YOUR choosing.
Metal pushing tool, preferably not copper…(too soft)
Do not use any Hand-Held, or Reciprocating Hammer!
Metal pushing device should have a serrated edge, on its pushing
face’.

First of all make very sure the stone in question is not
overpowering the bezel walls. WE do not wish to alter the bezel in
any way shape of form. This stone must almost sit inside the bezel
walls. Prior to letting the stone be placed inside and sometimes they
will get stuck inside and cause you much grief. Examine with your 10x
power loupe at times. Examine that all of the internal setting areas
are totally free of any casting irregularities, bubbles, extra shards
of gold, or any defects caused by the casting process. This is more
than important, this allows no adverse setting problems of the stone
due to breaking or chipping.

I would ask you to now to use a randomly selected round bur and
remove any extra gold that does is not needed. These pieces can occur
right at the bezel base or at the junction of the wall. Let your bur
run fast and this way it will almost polish as it’s drilling. I would
also run a bur along the base of the wall at the same time.

Please examine the stone in question, do YOU feel that the stone is
going to meet at the corners of the bezel? If not, YOU should adjust
the bezel wall…not the final shape of the stone. Both the stone and
gold must meet at the same location, just prior to tightening. Here
comes the easy part, with your Pillar file #1 (rougher cut) thin out
the very top of the bezel wall. This must be only at the very top,
why? Glad you asked, so ‘we’ the setter won’t be pushing too hard as
to damage the with undo pressure and break the stone. I normally file
at a 45degree angle on the outside bezel wall tip. I want to press
over with just enough pressure as to not to break the stone. Now
comes the very important area of this whole process. The Four
corners.

Once you have ascertained that the stone can be placed INTO the
bezel. Allow some time as to see just exactly where the corners will
meet, it is at this axis or section at eh bezel is just where you
must now drill a hole. This hole will prevent any touching of the
stone to the bezel wall. I call this the “Floating Corners”. NO METAL
MUST COME IN CONTACT AT ANY TIME DURING, OR AFTER SETTING. Let me
just say that these are the sides of the bezel wall that is
‘holding’.

Have you done your homework and judged for yourself how the bezel
wall and the base is cleaned? WE do not want any undo breakage of
this stone once the pressure is being put against the stone while
setting. I would at this point allow a smaller round bur and create a
side or oval opening of the four corners. This will allow some wider
distribution of the girdle mass of the stone and along the
bezel…I will now request that you use a #008 round bur and create
a bearing cut, or groove to allow if the stone has a slight girdle.
We are not speaking of a Cabochon in this case, but a faceted stone,
I presume.

To identify a ‘well prepared’ stone setting, please make sure if the
four corners are matching against the bezel walls. Are your newly
made bearing cuts in line and not deviating from the symmetry of the
girdle? If this is accurately accomplished, I would now place the
stone in the bezel. Hoping that the stone is not ‘rocking’…this is
due to an absence of the cleaning care with your round burs during
the preparation process. With this “hand-pushing” you can easily even
set an Opal, baring any internal inclusions.

Place your stone in the bezel, now with your metal pusher, not the
hammer at this point. Start to press the filed metal right beside the
actual corner, NOT AT THE CORNER at this moment. We are now pressing
over a total of “8 contacts”, not just four. These two “contacts” are
just on each side of the bezel corner, got this so far? You will have
little difficulty with the metal being shaved off at a 45degree
angle. Your pushing tool must be rocking over the metal towards the
stone. Do not let the metal pusher actually TOUCH the stone. With any
bezel, make sure all the gold is over and touching the facets of the
stone.

Now once the stone is being totally tightened all around the 4
sides, GENTLY and with great care, lightly press, or mold over the
actual corner and let the gold “sit against” the stone. But with
extreme care not to push hard over the stone, trust me, you will have
great anxiety if the stone breaks. Those strange words cannot be
mentioned on Orchid…:>)

Once the stone is now set and secured, use your finer cut, Pillar
file #2 cut and file to smooth-over the gold and remove most of the
“pushing marks”. Use a file against your finger pad, try not to let
your file touch the stone. Another way to damage the stone too. Once
most of the marks have been removed, use now your Flat edged Pumice
wheel with a #180 grit, and smooth the surface. There should me no
marks at this point to look at. With your Tapered, Pumice wheel just
do a ‘touch-up’ on any indentations surrounding the setting.

Remember, the FOUR corners are to be used only as an illusion, the
maximum holding is done by basically the FOUR walls.

Hope that this has been a help to all. Also remember this is my
perspective on “How set a Four-Cornered Stone”. This can be used as
an ‘alternative’ stone technique…Gerry Lewy!