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Edhelien
29-08-2014, 06:12 PM
Hi,
I need an advice with setting.
I bought this setting: http://www.cooksongold.com/Settings/18ct-Yellow-Round-Double-Gallery---Collet-2.5mm-R4d20-prcode-NN1-112
I wanted it for 2.5 mm black diamond. But the setting is little bit larger (2.6-2.7 mm) and when I place the stone inside, I can see a tiny rim of metal. That means setting is too big for 2.5mm stone. But i think it is too small for 3mm.
I am not experienced with this type of setting and I am quite confused. According to description it should be for 5pts (diamond?).

ps_bond
29-08-2014, 06:44 PM
According to my charts, 5pt is 2.4mm but never mind. When you say you can see a tiny rim of metal, do you mean the gallery? With commercial settings I usually expect to remove metal from the gallery to get the stone to sit low enough - it's more of a problem with deep-bellied stones that don't conform to the ideal cut for that shape though.

Edhelien
29-08-2014, 07:28 PM
Yes, the gallery. I probably can remove some metal and it needs stone-setting burr anyway, but I am worried that I ruin it.
Thanks.

Aurarius
29-08-2014, 09:07 PM
Just to make sure, are you saying that the 2.5mm stone already sits between the prongs all the way down on to the gallery? If it does then it sounds as if you won't have much leeway to remove material.
BTW, what's your main worry about using a setting burr specifically? Are you worried that it's the setting burr that will ruin the job, or that just removing material some other way may ruin it? Whatever happens, you'll have to create a seat for the stone, so material will have to be removed.
BTW 2, I've learned to use Cooksons measurements as only a rough guide to stone size, not a definitive statement.

Gemsetterchris
30-08-2014, 02:48 PM
If there is a gap between stone & claws don`t bother trying to set it.
If stone is touching claws you might get away with it but don`t cut a bearing into the claw..also burnish the outside edge of the gallery at an angle.

Ideally the stone should not quite be able to sit flat in the setting.

Edhelien
30-08-2014, 04:50 PM
Aurarius, no, not all the way down. I need to use 2.5mm burr or cut the bearing into the prongs (or both).
But then it will be too wide, because diameter of the gallery is bigger then the stone (something between 2.6 and 2.7 mm, stone is 2.54 or something like that).
The prongs are not fully outside of the gallery circle, they are partially in it. So the inner distance between two opposite prongs is smaller then the outer diameter of gallery. I don't know if it makes sense.
Burnishing outside of the gallery could help.

Gemsetterchris
30-08-2014, 05:54 PM
Even I'm getting confused now :D
Don't over complicate.
Clean up & burnish the outside & top of bezel nice & bright & minimize what you can see.
Don't drill anything for the sake of it just because your "supposed to" & only as much as needed if any.

Dennis
31-08-2014, 07:53 PM
It is possible to bend the prongs out a little too, but if you do decide to use a setting burr, please avoid one of those hairy Dremels.

You can mount your burr in a universal handle, such as Cookson 999AZM, oil it a little and turn it by hand. This will give you much more positive control. Dennis.

Gemsetterchris
01-09-2014, 07:08 AM
I`ve a job here today (in fact 3 of them), with too small stones.
So..I push the claw over as it is, rather than cut a bearing in the claw which would make the metal even further away & make things worse.
6525

Aurarius
01-09-2014, 05:35 PM
That's very interesting, Chris. I didn't know it was accepted practice, but clearly if the stones you've been asked to set are undersized for the setting you've not much choice. Do you have to do any compensatory filing on the outer edge of the prongs in order to make them more willing to bend in the place you want them to bend, or would this depend on initial prong thickness?

Gemsetterchris
01-09-2014, 05:57 PM
What's excepted is the final result :)
If you have a diamond or sapphire, pushing the solid claw against the stone will indent the gold enough to make a kind of bearing.
You need to judge if you can get away with it, sometimes It's not a good idea & looks a mess or just won't work.
A short fat stubby claw probably might not be moveable without cutting a bearing & the only option is a stone that fits properly.

You can bend the "rules" abit once you've learnt them & sometimes It's required.
You can't always have everything ideal unfortunately but it is of course better..

I use various rubber wheels these days to tidy up most jobs..

Edhelien
08-10-2014, 10:03 PM
Hi, it's me again :)
After a long time it is finally done.
Best advice was "Don't over complicate".
6712

Thanks again.
And thanks a lot for the tip on a burr handle. I don't have anything like it and now I see it as must have :) I was thinking about using hand drill or something similar for burrs for quite a long time (every time when I was cursing high rpm of my hobby drill) but I wasn't sure if it works.

susieq
08-10-2014, 10:25 PM
I think it looks beautiful Anna, well done. Loving the texture on the ring shank too.

Suse

Edhelien
08-10-2014, 11:11 PM
Thanks Susie, I am still learning basics of working with faceted stones.
Texture is done with old hammer personalized with saw.

Dennis
09-10-2014, 11:21 AM
I think the ring shank with its texture is beautiful Anna, but I am not a great fan of prongs.

Perhaps one day you will try a tapered rub over collet. You can buy them, or make your own. They have the additional benefit of not being so size sensitive. Regards, Dennis.

Tabby66
10-10-2014, 07:31 AM
Very nice result Anna!!

Nick martin
14-10-2014, 07:21 AM
That looks great Anna, and as you've just learnt, the uses for a dremel are fairly limited due to their high rpm.

Chris: interesting comments about prong setting stones and the indents made when pushed onto diamonds etc. Presuming that you always need to cut a 'v' groove when pushing against much softer stones right?

Nick

Gemsetterchris
14-10-2014, 08:30 AM
You should always have a bearing cut, this was an instance of having a too small stone where the stone sat inside the claws rather than "inside" the claws.:D
I make cuts are more shaped like a "7" for bigger stones.