Back to Ganoksin | FAQ | Contact

Invisible prong settings in CAD


#1

Anyone have any pointers on making an invisible prong setting in
CAD? Or even have a good example in a photo of one?

Thanks,
Aviva


#2
Anyone have any pointers on making an invisible prong setting in
CAD? Or even have a good example in a photo of one? 

Either I’m not understanding what you want, or you’re not
understanding what you want, at least in terms of the words you use.
Invisible settings do not have prongs. That’s why they’re invisible,
the metal holding the stones is all under the girdles between stones,
fitted into grooves cut into the pavilions of the stones, and
sometimes channel settings along the sides. Either way, no prongs at
all. What are you trying to make?

Peter Rowe


#3

Invisible prong or did you mean invisible setting techniques done in
CAD?


#4

Well, the buyer called it an invisible prong setting; as I am a
serious beginner at jewelry design, especially in CAD, I’m not sure
of much terminology, but I do know this:

overstock.com, not the best source for jewelers by far,
says that “Invisible settings are a modern solution for a sleek ring
design. Invisible settings are similar to prong settings, but they
hold the stone with prongs under the stone, rather than around it.
This method creates a ring that is sleek and minimalistic while still
having a traditional look.”

So if you know what they are talking about (if they knew what they
were talking about) and can help me out, that would be awesome. In
any case, if I have a stone that fits into a bezel, if I have prongs
that are hidden in the hollow body of the design to be pushed around
the stone to hold it, and then have a back to that design soldered,
is that practical? Would it even work? It would be a monster to
repair, wouldn’t it?

Anyway, in light of your reply, I guess a better question to ask is
what would you offer a buyer who requested prong settings because
it’s easier for their workers to fabricate, but wants them as
invisible as possible?

Thanks,
Aviva


#5
overstock.com, not the best source for jewelers by
far, says that "Invisible settings are a modern solution for a
sleek ring design. Invisible settings are similar to prong
settings, but they hold the stone with prongs under the stone,
rather than around it. This method creates a ring that is sleek and
minimalistic while still having a traditional look. 

Overstock is wrong. There are no prongs. The stones themselves have
grooves, a bit like tongue in groove flooring boards, cut just below
the girdle on the pavilion, usually two opposing sides, not all the
way around, though that too is done sometimes.

The invisible part of the mounting is a simple rim of metal almost
like a bezel before you cut a seat and drop the stone into it. A
narrow cut with a graver is made, splitting the top edge of that rim
so now the cross section would be like the letter Y, except not so
wide. (this assumes several stones side by side, and this rail will
hold two of them). when the stone is simply pressed down onto this
split edge, the edges deform and bend inwards, into the groove,
which then holds the stone. Single stones also grooved, can be held
much like bezels, except instead of burnishing the metal over the
girdle, you’re working it into the grooves below the girdle. It ends
up looking as though the stone was just sitting on the metal, not
held in by anything, thus the name, invisible setting. In the case of
multiple stones, often square stones looking a bit like a
checkerboard pattern, the stones are almost touching girdle to
girdle, with no metal extending up above the girdles. What’s holding
them in are those narrow flanges which have bent inwards into the
grooves in the stones. No prongs. And this type of setting work is
difficult enough to do, that precise fitting is critical. I doubt
you’d want to use the CAD to pre cut those flange edges. The graver
does it cleaner.

For your customer, I’d simply suggest that you try to keep the sizes
of whatever prongs you make, fairly minimal. Some CAD designs can
tend to sometimes make such parts a bit clunky and heavy, so this is
what you want to avoid. Tapering the setting so the lower sections of
prongs lean in under the stone, rather than being vertical, also
reduce their visibility and heavy look. But no matter how you do it,
prongs simply cannot be invisible. If you make them too light, they
simply won’t hold the stones securely enough.

If they don’t want to see visible prongs, perhaps you could suggest,
instead a very delicate bezel. Because bezels go evenly all the way
around the stone, You don’t see obvious “clamps” extending over the
stone, and breaking the outline. The bezel does come slightly over
the girdle, but to the same degree all the way around, so it may not
be obvious. They’re also not so prone to being snagged and pulled
back if thin and delicate, and for a bezel to let go, you have to
have some serious damage or have much of the metal worn off the top.
If the width of the bezel (looking down from the top) is narrow, and
only extends a little bit over the girdle, you can have a secure
setting with metal that remains delicate and minimal looking, yet
still secure.

By the way, if your clients really insist on a true invisible
setting, you might wish to try and dissuade them. Most of the jewelry
I’ve seen out there these days from commercial firms which are
invisible settings, aren’t worth crap. It’s not so hard for a
manufacturer to get fine looking invisible set work out the door.
It’s another thing entirely to have made it well enough so it will
hold up. This is a difficult technique to master and do really well.
And stones have to be critically well chosen or cut specially, to the
required size. Very little leeway there. However, there are plenty of
craftspeople (judging by the number of firms who offer such goods)
who seem to be able to crank out lots of invisible set work which
doesn’t quite meet the standards one might wish. Trouble is, because
the inadequate fitting or slopping work is on metal that you cannot
see, there’s no way to tell. And once those stones start to loosen,
it’s often almost impossible to repair then short of just dumping a
bunch of glue over them (yuk). Even sizing these rings can be very
risky to impossible.

Don’t believe me? Buy one of those invisible set things from
Overstock.com (which are there for a reason, remember), and size it
down one size. Then wear it a week and see how many stones have
become loose. And then try to find a jeweler who can promise to
properly tighten them again and ensure their safety.

Good luck.
Peter


#6

Aviva- There are no prongs. The girdle of the stones have a notch
cut into them. A very thin rail is in between the stones to hold them
into place. The stones are precision cut and everything has to be
very tight. No room for slop. The outside edge is set like a channel
setting. This technique is NOT suitable for rings that get every day
wear. Invisible setting is best for pendants,pin or earrings that
won’t get much wear. You will have to special order the stones with a
groove cut into the girdles. Go to a jewelry store that has theses
and take a close look at them.

After 42 years in the biz I’ve seen a lot of these. The rings are
difficult to size without popping stones. Once the stone fall out,
and they will, they are extraordinarily difficult to reset. I would
not own or wear one.

I’m usually more than happy to con newbies into trying something
new, in this case, I’d say “Run. Run away as fast as you can.” Oh, and
take with a grain of salt the word of someone who is trying to sell
you jewelry as an expert at anything except selling.

Have fun and make lots of jewelry.
Jo Haemer
www.timothywgreen.com


#7
But no matter how you do it, prongs simply cannot be invisible. If
you make them too light, they simply won't hold the stones securely
enough. 

This is a very important point. Security of the mounting is
overriding any other consideration, so prongs must be strong. As far
as invisibility goes - the prongs must not be offensive to the eye. A
lot of settings done very crudely, so the reaction is to make prong
disappear. Cannot be done. Prongs must be part of the design, and
aesthetics should play a role in what setter does. Than prong
visibility would not be an issue.

Leonid Surpin
www.studioarete.com


#8

Thanks Peter, Jo and Leonid - I forwarded your concerns to my client
(who happens to be my uncle giving me my first break) and I
appreciate it.

I think the bezel idea is the best route, but we’ll see what he
wants to do.

Aviva


#9

Dear All,

If you want to see some beautiful invisible settings go to:

http://www.ganoksin.com/gnkurl/41

I saw a model of one of the double rings from this company once.
They make the channel of diamonds with a steel or platinum support
bar between the stones. The channel is made to perfection.

Look for some of the double and triple row diamond rings.

Regards,
Todd Hawkinson
Southeast Technical College