@Kenny & others - Diagonal cut tension ring design w/ .30 ct F VS1 ACA (Bruce Boone) - input needed

[crbl999]

My diamond arrives today!! With the help of Brittany at WF I selected a .30 F VS1 ACA.

https://www.whiteflash.com/loose-di...clarity-round-ideal-cut-sku-a4557698?a_aid=PS

Finalizing my ring design and here is what I have so far. @kenny I know you have worked with Bruce and have extensive experience with tension rings. Anything you would change or add to the below?

My main questions are gap between the culet and bottom of the ring? Set diamond flush with band or slightly above? If slightly above, how high would you set it (where the bezel facet, star facet, and upper half facets meet)?

1. Brush black zirconium
2. 5mm width
3. Comfort fit
4. Diagonal cut (backslash orientation)
5. Slightly rounded diagonal cut tips (just enough to remove the sharp points)
6. Put the finger hole offset away from the stone side. That leaves the stone side slightly thicker, the bottom thin, and the space between fingers to be mid-way between.
7. .5 mm gap between the culet of the diamond and the bottom of the ring (portion that touches my skin)
8. Diamond set so table is higher than the ring to allow maximum light exposure while still being securely set.

 

[kenny]

To answer I need to do some homework/research, but I'll be back.

 

[adlgel]

Do you think you need to specify the angle of the diagonal cut across the top of the ring? Do you want it to be effectively a 45 degree angle or something different?

 

[crbl999]

Do you think you need to specify the angle of the diagonal cut across the top of the ring? Do you want it to be effectively a 45 degree angle or something different?

I thought about specifying an angle, but there is a trade of too much angle and metal contacting to secure the stone. I will certainly make mention of it in my notes.

Bruce also has this design. It is a curved diagonal cut. I'm happy with this amount of angle, just need to eliminate the curve.

https://boonerings.com/collections/stone-settings/products/s-curves

 

[kenny]

First @crbl999 I love everything about the diamond you chose.

1. Brush black zirconium ...

Any ring can get scratched and eventually suffer wear to the surface.
I'd find out whether that could expose zirconium (which is a silver/white metal) below the surface.
I'd ask Bruce (and others), If you cut a black zirconium ring perpendicular to the ring (as you'd cut a tree trunk to see the growth rings) would the metal be black all the way to the center? Or is the black only at the surface?

2. Ring width of 5 mm ...

I like that 5 mm metal width for a 4.3 mm diameter diamond offers more impact protection for the diamond compared to the diamond over hanging or being flush with the sides of the ring.
Though, obviously, if you bang your ring on the corner of something hard, at exactly the right (actually wrong), place the diamond could still be chipped. So no matter how safely and smart your ring design is, still be careful with it, especially if you're are rough with your hands.

3. Comfort fit

I think comfort fit means the edges of the sides of the ring that touch your finger are rounded for comfort.
I like that and think that's what I have.
Yes the metal edges of the gap being smoothed down is a good idea for comfort.
How much should they be smoothed down?
I'd discuss that with Bruce.

4. Diagonal Gap

First let me state that Tension setting is a misnomer.
According to Physics, tension is the force that pulls on a something, but compression is the force that pushes on something.
A tension setting does not pull on the diamond.
It pushes on it.
If it pulled, the diamond would immediately fall out.

A 45 degree gap would probably be a no-go for me.
I'd get the usual 90 degree gap.
Why?
I may be being overly OCD, but I'd have concerns about the magnitude of the force holding the diamond in place.
A tension setting must hold the diamond in place as securely as possible.

I'm not a licensed mechanical engineer but I worked over two decades surrounded every day by engineers of all specialties.
Over the years I attended a zillion design reviews where the mechanical engineers would look for weaknesses of proposed designs.
So I have experience of what kind of things they'd raise red flags about - and that gap's angle is one.

I'm not a degreed mechanical engineer, but I suspect the gap having an angle other than 90 degrees would exert less pressure on the diamond than a 90 degree angle would.
The 45 degree gap may be safe enough, and I'm just being overly careful.

If I'm paying the big bucks for a nice real diamond, I'd go with safety over cosmetics.

5. Rounding metal edges of the gap ...

Yes, good idea.

6. Drill finger hole offset away from the stone side...

Sounds good but I'd ask Bruce whether the ring being uniform thickness all around its full circumference results in more force to hold the diamond in place. If not, discuss options. As they say a chain is only as strong as its weakest link.

7. Gap between culet and skin ...

More gap makes the diamond sit higher, but too little gap lets the culet touch the skin. I'd discuss this with Bruce. I have no way to measure mine. Keep in mind finger skin can bulge up into the gap ... and a chubby finger will bulge up more than a lean finger.

8. Diamond table above ring's surface ...

Yes, more light getting in and out is more visually desirable. It's the main benefit of a tension setting. Of course there is a compromise between the diamond's table getting banged by being higher vs. improved light performance. This is another point to discuss with Bruce.

 

[crbl999]

First @crbl999 I love everything about the diamond you chose.

1. Brush black zirconium ...

Any ring can get scratched and eventually suffer wear to the surface.
I'd find out whether that could expose zirconium (which is a silver/white metal) below the surface.
I'd ask Bruce (and others), If you cut a black zirconium ring perpendicular to the ring (as you'd cut a tree trunk to see the growth rings) would the metal be black all the way to the center? Or is the black only at the surface?

2. Ring width of 5 mm ...

I like that 5 mm metal width for a 4.3 mm diameter diamond offers more impact protection for the diamond compared to the diamond over hanging or being flush with the sides of the ring.
Though, obviously, if you bang your ring on the corner of something hard, at exactly the right (actually wrong), place the diamond could still be chipped. So no matter how safely and smart your ring design is, still be careful with it, especially if you're are rough with your hands.

3. Comfort fit

I think comfort fit means the edges of the sides of the ring that touch your finger are rounded for comfort.
I like that and think that's what I have.
Yes the metal edges of the gap being smoothed down is a good idea for comfort.
How much should they be smoothed down?
I'd discuss that with Bruce.

4. Diagonal Gap

First let me state that Tension setting is a misnomer.
According to Physics, tension is the force that pulls on a something, but compression is the force that pushes on something.
A tension setting does not pull on the diamond.
It pushes on it.
If it pulled, the diamond would immediately fall out.

A 45 degree gap would probably be a no-go for me.
I'd get the usual 90 degree gap.
Why?
I may be being overly OCD, but I'd have concerns about the magnitude of the force holding the diamond in place.
A tension setting must hold the diamond in place as securely as possible.

I'm not a licensed mechanical engineer but I worked over two decades surrounded every day by engineers of all specialties.
Over the years I attended a zillion design reviews where the mechanical engineers would look for weaknesses of proposed designs.
So I have experience of what kind of things they'd raise red flags about - and that gap's angle is one.

I'm not a degreed mechanical engineer, but I suspect the gap having an angle other than 90 degrees would exert less pressure on the diamond than a 90 degree angle would.
The 45 degree gap may be safe enough, and I'm just being overly careful.

If I'm paying the big bucks for a nice real diamond, I'd go with safety over cosmetics.

5. Rounding metal edges of the gap ...

Yes, good idea.

6. Drill finger hole offset away from the stone side...

Sounds good but I'd ask Bruce whether the ring being uniform thickness all around its full circumference results in more force to hold the diamond in place. If not, discuss options. As they say a chain is only as strong as its weakest link.

7. Gap between culet and skin ...

More gap makes the diamond sit higher, but too little gap lets the culet touch the skin. I'd discuss this with Bruce. I have no way to measure mine. Keep in mind finger skin can bulge up into the gap ... and a chubby finger will bulge up more than a lean finger.

8. Diamond table above ring's surface ...

Yes, more light getting in and out is more visually desirable. It's the main benefit of a tension setting. Of course there is a compromise between the diamond's table getting banged by being higher vs. improved light performance. This is another point to discuss with Bruce.

@kenny
Thank you for your thoughts and thorough response. It is appreciated!

I have included my email conversation with Bruce below.

After thoughts: The ring will be made of black zirconium which is harder than platinum (~7.5 mohs vs. ~4.5 mohs, respectively). Many people have their diamonds set in 4 prong gold or platinum settings. IMO, these are more likely to get bent and cause a diamond loss than 2.15 mm thick and 5 mm wide black zirconium ring. I diamond loss due to a bent prong does happen, but even then it is not common. Based on these thoughts I’m not as concerned about an ~45 degree diagonal cut or the offset thickness of the ring. If it was an Octavia I may have arrived at a different conclusion.

@kenny I'm normally a function over fashion kind of guy, so this is a new position for me. Are my thoughts reasonable or am I too focused on the cosmetics and comfort?

Crbl999:
Three more questions:
1. Does the diagonal cut apply less force on the diamond compared to a 90 degree cut (i.e. your Classic Round Tension Ring)?
2. Does the offset thickness of the ring (thicker on stone side) place less force on the diamond compared to a ring that has uniform thickness all around?
3. Is the black zirconium subject to fading or wear? How scratch resistant is it? Is it black throughout or just a layer?

Bruce:
It's hard to put a number on the force of a diagonal cut versus perpendicular cut. It should be a little less. There will be less force on the offset ring versus a full thickness ring, as the ring is thinner at bottom and will flex more easily than one of full thickness.

For the black, there's no such thing as a black metal. It's always some sort of oxide coating. The coating on zirconium is pretty tough as far as those go, with a Mohs hardness at around 7.5. If it sees harder things constantly rubbing on it like hardened steels or harder minerals, it might eventually over years show a little wear. It likely won't ever wear through though.

Crbl999:
The word 'flex' makes me nervous. With the hardness of the ring, would it take a significant amount of force to flex the ring open? For example, simply hitting the ring on a counter edge or metal door frame?

I'm probably over thinking it. I would like to think my hand/finger would be crushed or broken if the ring was flexed enough to lose the diamond.?.

Bruce:
Yes, flex is a relative term. It does take a lot of force to open the prongs. They are preloaded to a gap smaller than the stone, opened with special tools, and the ring wants to go to the original dimension and firmly grips the stone.

 

[kenny]

@crbl999 you asked, "Are my thoughts reasonable or am I too focused on the cosmetics and comfort?"

I'm afraid the word, "too" makes your question unanswerable.
That wording implies there is one single right way to be, that applies to everyone.

But people vary.
What's too anything for one person, is not enough for another person.
Some are extremely detail-oriented, OCD, and suffer (or benefit) from analysis paralysis (as do I).
Others don't bother digging into the nitty gritty details, just go with their gut, and all they need is trust in the seller.
Neither type of person is a better way to be; people just vary.

On this project you've done due diligence.
I have raised as many reasonable concerns as my experience can imagine, and they have have been addressed by Bruce.
If I were you, at this point, I'd ship that beautiful ACA to Bruce and enjoy the results.
I think you're gonna be thrilled!

When you get the ring please tell us your first reaction, the reactions of others, and post lots of pics.

 

[crbl999]

@crbl999 you asked, "Are my thoughts reasonable or am I too focused on the cosmetics and comfort?"

I'm afraid the word, "too" makes your question unanswerable.
That wording implies there is one single right way to be, that applies to everyone.

But people vary.
What's too much for one person, is not enough for another.
Some are extremely detail-oriented, OCD, and suffer (or benefit) from analysis paralysis (as do I).
Others don't bother digging into the nitty gritty details, just go with their gut, and trust the seller.
Neither type of person is a better way to be; people just vary.

On this project you've done due diligence.
I have raised as many reasonable concerns as my experience can imagine, and they have have been addressed by Bruce.
At this point. if I were you. I'd ship your beautiful ACA to Bruce and enjoy the results.

I think you're gonna be thrilled!

Please post lots of pics, let us know your feelings, and the reactions of others.

I'm detail oriented which often leads to over analyzing. When I take a step back things become more clear and easy.

Working out the details to send my stone to Bruce and move forward with this project. I'm going with comfort and cosmetics.

Thanks for your input! I will be sure to post pictures when I get the ring.

 

[crbl999]

Finished ring pictures and hand shots are in this thread:
https://www.pricescope.com/communit...bruce-boone-diagonal-cut-tension-ring.279973/