Flush setting in a dome surface???

Hi All,
I'm working on an order, where I'll flush set a 3mm faceted blue zircon in a sterling silver bar necklace.
I will solder two layers of 18g sheet (approx. 1mm each layer) together (to add more depth for the stone), then will flush set the stone in the center of the top layer.
My concern is my two layers together measure approx. 2.03mm. However, the depth of the two stones I have to set is ~ 2.05 and ~2.06mm (my backup stone in case one breaks in the process is 2.12mm). The math just doesn't add up-- If the silver surface is measuring 2.03, but the depth of the stone measures 2.06, will the very tip of the cutlet be slightly sticking out of the backplate?
Once I solder them together, will that add enough more depth to make it work?

Having this concern, I thought I might dome the top layer, so as to add more depth. However, I've never tried to flush set a stone inside a domed surface. Is this possible? Will I run into any problems soldering a dome on top a flat surface, then drilling my hole through it (pressure inside?). Will there be enough surface area for the dome to successfully solder to the flat backplate?

Any other creative solutions or ideas?
Please advise! Check out the pics I've attached for reference. Thanks so much!

-Heather

Attachment 12625Hi. This is a 3mm cz flush set into 1mm silver sheet. I slightly domed the front and soldered it to a back plate then flush set the stone without any trouble. You just have to make sure you keep your drill etc at 90 degrees to the curve. If you’re really worried that your dome may buckle you could use thermoplastic to support it.

Kelltz has given you your answer, but you are still at risk of accidentally going right through your top layer and loosing your bearer.

I think you would be OK with your first proposal, for two reasons:

1. Soldering two layers together, increases the thickness by a little more than just the sum of the parts.
2. If you aim just to cover the girdle of the stone when setting, the table will stand a fraction above the surface of the metal. so you won't need the whole depth of the stone.

You can prove all this by experimenting with copper before you commit.

The real mystery is why you are not just adding a thicker patch behind. It does not have to be by much and it can be quite small, maybe in the shape of a heart, or a star. A secret only the wearer will know about. Dennis.

Quote:

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Originally Posted by Kellz

Attachment 12625Hi. This is a 3mm cz flush set into 1mm silver sheet. I slightly domed the front and soldered it to a back plate then flush set the stone without any trouble. You just have to make sure you keep your drill etc at 90 degrees to the curve. If you’re really worried that your dome may buckle you could use thermoplastic to support it.

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Thank you, Kelltz! Good to know it can be successfully done. I may have to experiment with that.

Quote:

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Originally Posted by Dennis

Kelltz has given you your answer, but you are still at risk of accidentally going right through your top layer and loosing your bearer.

I think you would be OK with your first proposal, for two reasons:

1. Soldering two layers together, increases the thickness by a little more than just the sum of the parts.
2. If you aim just to cover the girdle of the stone when setting, the table will stand a fraction above the surface of the metal. so you won't need the whole depth of the stone.

You can prove all this by experimenting with copper before you commit.

The real mystery is why you are not just adding a thicker patch behind. It does not have to be by much and it can be quite small, maybe in the shape of a heart, or a star. A secret only the wearer will know about. Dennis.

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Thanks, Dennis! It was my understanding that since this is such a small stone, 3mm, it's imperative the table is exactly level with the metal surface. Is this not so? And that is a nice idea of adding something behind it. I don't think I can do that though since the back has a stamped date on it (shown in pic)...

I think I may have to experiment with copper, but I have a feeling the flat disc will work, and am now wanting to try it in a dome too for fun and practice!
I thought about asking my client which look she prefers aesthetically, but then decided to just choose myself based on what will actually work so the stone fits right! She's expecting it to be flat, bc that's the style I've made her before in a ring, but will inform her otherwise if I have to change it to dome.

Attachment 12628

Yes you're right HM. It's bad enough having this discussion with yourself, without getting another party involved.
I'm sure an experiment with coper will resolve the issue quite quickly. Dennis.