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Setting for a cushion-cut stone that needs light


#1

I have recently lucked into a really gorgeous 4.5 ct deep red spinel
in a cushion cut, and I’d like to create a gold setting for it for a
ring. It’s a really nice deep blood red, and has a great cut with a
deep pavilion, and lots of sparkle. I think it will look best in a
setting that will let in more light, but I’ve only done bezel
settings. I’ve done some nice bezel settings for smaller faceted
stones, but I haven’t done prong settings yet. I don’t think a bezel
setting will let in enough light, unless someone has an idea on a
modified bezel that could be opened up to show a lot of light. I’ve
been reading though John Cogswell’s Creative Stonesetting book, and I
think either a crown or basket setting would do best, but being my
first stab at prong-type settings, I’m not sure. He’s got
instructions for how to make a basket setting for a square/cushion
stone, but not a crown setting, just instructions for a round stone.
Can you adapt those instructions to do a crown setting for a cushion
stone? I really do like the idea of a crown setting for the stone. If
anyone has any other ideas on a setting for this stone that would do
best, and how I can figure out how to do it, I would greatly
appreciate the advice. A pretty stone is a great inspiration to
learn!

Thanks for any help,
El Phillips


#2
He's got instructions for how to make a basket setting for a
square/cushion stone, but not a crown setting, just instructions
for a round stone. 
Can you adapt those instructions to do a crown setting for a
cushion stone? 

It is never a good idea to try something that you never done before
on good stone. Practice should be done on material that you do not
care about. Just yesterday I have published next installment to my
blog http://www.ganoksin.com/gnkurl/ep804y

where I am using my old video about making engagement ring, using
crown setting. You have square stone, so instead of round cone, you
would need a square one. The process is the same, with an additional
step of forming square out of round.

If you need more details on crown setting construction, that my DVD
http://www.ganoksin.com/gnkurl/1ea

Coronet Cluster has step by step instructions. Basket setting is more
difficult, but not unsurmountable. My another DVD Balerina ring has
step by step instruction on how to do it.

That said, I would not use either of these techniques on small
square stone. Neither crown, no basket setting go together with
square stone. What I can suggest is Roman Arch setting, which is
derived from Crown setting, but design is more appropriate for square
stones.

Go to my website, where I have a write up to help people with
Eternity Ring fabrication. On page 3 of that write up
http://www.ganoksin.com/gnkurl/1f1

I give examples of variations on galleries that can be used. The
third one is Roman Arch.

Leonid Surpin
Studioarete.com


#3

I of course completely disagree with Leonid- ALWAYS TRY something
you have never done before…

Anything can be adapted to your needs - just make good design
sketches and use some cheap wire (same gauge and shape you will end
up using for the finished design) to make a “prototype” to see if
your original design combining the elements you like from the
settings you mentioned will work for your purposes. Of course for
prong settings (or any other settings) Foredom’s All Set system is a
favourite bench tool of mine. You can do anything with it, with great
results, quickly- well, after a few practise settings to learn the
tool’s potential. With prong work you will get excellent results the
first time as the tool does the work for you - provided the
measurements are 100% accurate and you have tried the stone in it
before closing the prongs around a stone…(you could always make a
copy of the stone to use as a tester while working out your design
details).

Another idea is creating a wax and having it cast for you. or
casting it yourself.

A tension or tension like setting will let in the most light- but
sounds a bit more 'modernist" than you want. Channel settings can be
seen in any number of vendors catalogues as well- not only do they
let in a lot of light but can be attached to any shank you can dream
up. getting an idea of the way they seem to be a cross between a
tension setting and a “vise” holding the stone on two edges may give
you some ideas too…

Bottom line- have fun and don’t think for a second that it must fit
into any pre-fabricated style- so play around with your sketches,
look through some design award winners and coloured stone magazines
for inspiration then it may just come to you- the perfect way to
show off the stone in an aesthetic that appeals to your sensibilities
and design approach… there is no right or wrong. and consider the
Foredom AllSet system as a bench tool investment- it will make any
setting work you may do perfect- no mismatched prongs, no non-level
channels, no off spacing between stones (as in an ‘infinity’ style
band/stack ring), or imperfectly milled parts (the master set comes
with a milling table)… I don’t work for Foredom/Blackstone, but
LOVE the AllSet system and could make a career going around the world
demonstrating it to jewellers (then selling them and getting a
commission!!)… Good luck on your project. rer


#4

not sure how hard spinels are, but if the stone will survive in a
tension setting, that will let in most light possible. In my
opinion. I have NOWHERE near the experience of the masters on this
site, but I do wear a gorgous tension set diamond ring, and it
always brings compliments.

Blessings,
Sam Kaffine


#5

It would be rather tricky to tension set a spinel. Although I am a
great one for just getting dirty and trying new things, I do not take
chances with stones that are one of a kind, or stones I cannot afford
to replace.

Tension settings to work properly, need a special alloy available by
the folks who invented it.

If you have never set anything in prongs, I would recommend that you
practice first with some CZs.

Have fun and make lots of jewelry.

Jo Haemer
timothywgreen.com


#6

Thanks for the advice Leonid! I’ve only been able to give a quick
look over all your so far, and I probably should get one
of your DVDs! But I was looking over your new blog entry, and I’m
wondering why you couldn’t just take a round crown setting and shape
it as four prongs for the corners of the cushion, like the diagram
you have with the square shape in it? I know I’d have to draw my
stone as round by filling out my square cushion in order to cut the
right shape for the cone in the sheet metal, but I don’t see why the
crown setting itself has to be square unless I want more than four
prongs. I actually thought about doing a modified square bezel where
I cut away material down to the shoulder bezel except for in the four
corners, and that would definitely have to be square. But it would
still pretty much keep the whole pavilion hidden where no light would
get to it. It seems like the crown setting would both lift it up and
be open enough to allow the light to the whole stone. And I do have
some not-as-fancy square cushion stones that I could practice on with
silver settings. Silver isn’t quite as scary to mess up as gold. I
may say “sh@#!” when I fry silver, but I say a lot worse stuff when I
fry gold.

Thanks again, and I’ll take any help you can give me!
El


#7

Thanks R. E. Rourke for your input also, and yes, you are right that
I think a tension setting would be too ‘modernistic’ for the rest f
the design for the ring. It’s going to have a bunch of frilly design
stuff in it (that’s my technical description, lol), and from the
beginning I thought the look f a crown setting would work. And while
I do NOT want to hurt the nice stone or fry some gold, you can ask
anyone who’s ever taught me anything that I really want to learn "
they’ll tell you that my having no idea what I’m doing has NEVER
stopped me from trying, lol! It’s why my trainer will sometimes just
come up with stuff like making me jump with the reins under my
horse’s neck; she knows I’ll go, “Oooo, kind of scary. Oh well,
what’s the worse that can happen?” So I’ll try to plan everything
out as well as I can beforehand, and I’ll attempt it first with less
expensive metal, but I’m glad to try and jump right in and try
something. And that Allset is starting to look more and more
tempting to me.


#8
Thanks for the advice Leonid! I've only been able to give a quick
look over all your so far, and I probably should get
one of your DVDs! But I was looking over your new blog entry, and
I'm wondering why you couldn't just take a round crown setting and
shape it as four prongs for the corners of the cushion, like the
diagram you have with the square shape in it? 

If you are asking if a cone can be shaped into square pyramid, the
answer is yes. If you asking to do it to a ready setting, than the
answer is no. The metal will not deform evenly and prongs will be
misshapen.

Leonid Surpin
Studioarete.com


#9

Hi

quality reading comprehension obviates unctuous mistakes, such as
the following.

I of course completely disagree with Leonid- ALWAYS TRY something
you have never done before.. 

Perhaps that is, sir, because you did not comprehend the post.
Leonid

It is never a good idea to try something that you never done before
on good stone. Practice should be done on material that you do not
care about.

Wise words of advice, but misread by you sir, Leonid did NOT say to
NOT try something new, just don’t do it on a precious stone to start
with.

Also sir you are not a master goldsmith who worked for Tiffany.

You do not need to spend serious money on the Foredom All set
system. Unless you will set hundreds of stones.

It is a high quality high production tool. Which most of us do not
need.

A tension or tension like setting will let in the most light- but
sounds a bit more 'modernist" than you want.

Current tension setting tech specs would have only gems 9 or more on
mohs scale. And they need to have very good tenacity as well.

So that means diamonds, rubies, sapphires and moissanite. That
definitely leaves out your spinel. As it would not withstand the

more than 10,000 pounds per square inch the spinel would be subject
too.

Also I doubt you would have the specialised equipment to produce the
the required strength in the alloy.

Try this:

Buy a few CZs the size and shape of your spinel, cost you about $5
each.

Sight unseen, but your spinel could be worth some decent money. Also
practise makes perfect.

Make the design(s) in silver and enjoy and learn from your mistakes.
Sell them bling is still in.

Take the design you like the best and matches your skill set, then
set the spinel in 18kt yellow. And, because of your practice rings
you will have a a really fine piece of jewellery.

If I was making the ring I would google cushion cut stones in rings
and pick the designs I liked the best.

And then make them with the CZs, before going on to gold.

We are lucky that a master craftsman like Leonid freely shares his
advice, not matter that it may annoy the ignorant.

Who want, to use a colloquialism, “To teach granny to suck eggs.”

Look at Leonid’s tool making blog it will change the way you set.

All the best and enjoy the challenge and the refining of your
skills.

Richard


#10
Make the design(s) in silver and enjoy and learn from your
mistakes. 

I agree that this is the best way for me to go. I need to force
myself to be patient and make those mistakes on other stones before
I go on to my spinel. And I’m way ahead of you on googling cushion
cut stones in rings. I’ve been doing that for days. The problem is
that most seem to be set in very unsubstantial looking, cast basket
settings. But I’ll keep looking through them. And thanks again for
your help.

El Phillips


#11
If you are asking if a cone can be shaped into square pyramid, the
answer is yes. If you asking to do it to a ready setting, than the
answer is no. The metal will not deform evenly and prongs will be
misshapen. 

That makes sense. So I must make a square cone. Would the best way
to make the square be to make the metal blank for the cone as if it
were the regular round cone, then bend it in four equal, flat
sections for the sides of the stone? If there is a detailed tutorial
somewhere about how to do this, I would love to look at it. And
thank you again Leonid, and everyone else who has been giving me
advice on this.

El Phillips


#12
That makes sense. So I must make a square cone. Would the best way
to make the square be to make the metal blank for the cone as if
it were the regular round cone, then bend it in four equal, flat
sections for the sides of the stone? If there is a detailed
tutorial somewhere about how to do this, I would love to look at
it. 

I am not aware of any tutorial, which definitely would be helpful
here.

I shall try to describe the process at the risk of proving the old
adage the one picture worth a thousand words.

The best way to proceed is to compute a template, which when bent
would form square pyramid, or prism of you like, of required
dimensions.

Decide on setting height. Let’s take for argument sake 9mm. The
stone width let’s take 6mm for convenience. So our template should
have be composed of 4 triangles, each having 6mm base and 9mm height.

This represents a class of templates which derived from a disk.

We take a disk and draw a line from disk center to it’s perimeter.

This is nothing more than a radius. From the point of intersection,
start laying our 4 distances 6mm each. Now, join all these points
with straight lines, and also join every point with center of the
disk. That is the whole template. It should be cutout and bent along
the lines running from the disk center. One thing I did not mention
is how to determine the disk radius.

This is the only part which requires computations. Once radius is
known, the rest is trivial.

To determine radius, draw a triangle with base 6mm and height 9mm.

It is a good idea to use multiplier of 10 for clarity, so the
triangle will be 60mm base and 90mm height. Mark triangle vertices as
A, B, and C.

Drop a perpendicular from top vertex to the base and call
intersection as D. So vertices would be marked as leftmost as B; top
as A; rightmost as C; and intersection of base and perpendicular as
D. Consider triangle ADC. It is right triangle, which means that we
compute length of AC, which is exactly the radius that we are looking
for. Because it is right triangle, AC is hypotenuse of this triangle
and can be computed using following formula, - AC = sqrt(AD^2 + DC^2)
substituting our dimensions we get, - AC = sqrt (9^2 + 3^2) = sqrt
(81 + 9) = sqrt(90) = 9.486 or approximately 9.5mm.

This is the radius of disk, which yields required template.

There is one complication. We have to account for thickness of
metal.

Here is what we do: Let’s say we will use 0.8mm. The way the pyramid
will be formed is by engraving the lines to triangular profile to
allow for ease of bending.

The depth of these grooves shall be 0.6mm. Since grooves must be 90
degrees, the wall inclination is 45 degrees, which means that width
of such grooves is twice the depth, or 1.2mm. That means that our
template should have not 6mm base, be 7.2m for 2 inner triangles and
6.6mm for outside. For the purposes of calculations 6.6mm must be
used. This of course is thickness depended. Difference thickness
would required different numbers.

If someone would find this post a bit too much, I am in complete
agreement with you. It should have been done with charts and graphs
to illustrate the concept. But I am leaving for Rome and have no time
to do a blog post. May be when I come back…

Leonid Surpin
Studioarete.com


#13

Eleanor, the book; 'Silversmithing and Art Metal" by Murray Bovin
has the formula with illustrations for making a cone as well as a
pyramid on page 45.

Sam Patania, Tucson


#14

I shall try to describe the process at the risk of proving the old
adage the one picture worth a thousand words. I shall try to describe
the process at the risk of proving the old adage the one picture
worth a thousand words… [lots of calculations and awesome stuff]."

Thank you very much for this Leonid. And yes, it is a little
complicated for me to figure at the moment. I was a studio art major,
so pictures work better for me than just math. But I will try to
figure it out. And if you did a blog post about this once you get
back from Rome, I know I and many other people here would be very
grateful! And I hope you have an amazing time in Rome. I envy you
getting to go there!

Thanks again,
El Phillips


#15
Eleanor, the book; 'Silversmithing and Art Metal" by Murray Bovin
has the formula with illustrations for making a cone as well as a
pyramid on page 45. 

“The rings book” by Jinks McGrath has some tips on this too.

Regards Charles A.