Pearl Ring Cast 1888 US Dollar Coin Silver Beginner Sanity Check

[Wine]

Hi all,

I personally hate it when beginners ask vague questions on a forum and expect others to do all the work for them, however, I also know that a huge text over-explaining my issue may turn some people off, so I have a short version and an extended version of my dilemma(s):

Short Version
I am very new at all of this and don't know if there are any a huge flaws in my plan. I would like to cast a pearl ring. Metal is from 1888 Morgan US Dollar (90% Silver 10% Copper). Based on my design, I'm thinking there will have to be some level of machining after casting. Most of the processes I'm considering involve casting a solid cylinder on top of the ring, milling/drilling out a hole from the inside/center of the ring up into the cylinder, setting the pearl up into the hole in the cylinder, and then riveting a plug in to keep the pearl in place. See below for drawings & specifics.

I'd like a nod of approval from veterans before attempting any of this. I have no idea if there are massive problems with my plan. I also welcome any and all suggestions and answers to questions below, and even any answers to questions I didn't ask but should have.

Long Version

My Skills:
For most intents & purposes, I have no real experience making jewelry. As the son of an engineer and nephew of a machinist, I'm fairly handy and somewhat familiar with what it takes to design and work with metal. I also have a lot of tools at my disposal, but not necessarily tools that are strictly intended for what I plan on doing.

Small Backstory:
Around 8 months ago, I bit into a pearl while eating a raw oyster across the table from my girlfriend. We ended up paying our bill and leaving the restaurant without the pearl. Upon discovering the rarity of finding a natural pearl, we both began to stew with regret. She called the restaurant, nobody had found it. Without telling my gf, I decided to go and look for the pearl myself. I found the pearl on the ground below the table. My girlfriend still doesn't know I ever went back and she thinks the pearl is lost forever. Even 8 months later, she still talks about how sad it is that we lost it. At one point, we even discussed how, if I had made her a ring out of it, it would be her favorite piece of jewelry.

The Pearl:
The pearl is small (around 2mm at it's widest) and fairly oblong/not spherical. The coloration looks decent to a laymen. I don't have a pic at this time but if you guys think you'd like one I can upload one later.

The Metal:
We were both born in 1988, and we both recently made fantastic memories together in New Orleans on a vacation. I would like to use the silver from one or two 1888 New Orleans Minted Morgan US Dollar Coins. Per Wikipedia, it looks to me like this coin is: 90% Silver 10% Copper

The Design & Plan:
A few months back I read a bit about different types of casting and I tried to develop my design within the limits of casting in general, and more specifically, within casting methods which would allow me to keep my wax. I remember making a realization that the design I'm about to present to you had a problem and would not cast well, but I cannot remember what my concern was and It may have been unfounded.

Before I start to explain my process ideas, here are some pics of the design to help you visualize:







My design has the pearl set in a sort of cage with three bars. I have several different techniques I’m considering. Most involve casting first and some machining on the ring after. I think there is a fairly high chance of me failing the first time during casting so If possible, I'd like to not lose my original wax during the casting process.

I think I would like to cast the general shape of the ring with the cage setting being cast as solid. Then I’d like to mill/drill a hole up into the cage setting from the bottom/center of the ring.



In the above picture, the orange represents the pearl, the green is a plug holding the pearl in place (also putting slight pressure on the pearl, so as to prevent movement. The purple is a rivet holding the plug in place.

When it comes to the cutout/scoops in the setting/cage, the ones which reveal the pearl, I’m not sure whether it would be better to mill or cast them. If I mill them, the wax blank would then be pretty simple (Wax Style A) and I could maybe consider a lost wax casting method. If I cast them I may be able to scoop the wax more precisely than the silver and end up with a better result (Wax Style B). It’s also possible that milling would be more precise and give a better result. There may be other strengths/weaknesses I’m forgetting or unaware of.



One of the biggest problems with what I have presented so far is that with a complete circle ring, I cannot come up from below with a drill because the bottom of the ring is in the way. There are several ideas I have for how I could work around this problem and still do the milling & drilling, but I'm not sure any of them work well because: I cannot expose the pearl to heat, I'd like to cast a full circle ring without a break, etc.

Tools Available:
Milling Machine w/round table attachment for spinning piece , Oxy acetylene torch, probably a propane torch, hand/wood carving tools, pretty much any other basic machine shop tools

Timeframe:
I’d like to finish this project before July 13th 2017.

Challenges & Questions:
A) Do you all see any major problems with any of what I have told you? Are there flaws with my process, design, or anything else?

B) Is the Metal suitable for my intentions?

C) What sort temperature do I need to achieve to melt this metal? Would an Oxy Acetylene torch be suitable? Or maybe just a propane torch? What kind of crucible?

D) Do you think this kind of setting will secure the pearl enough that it will not move around and therefore will not deteriorate over time? Or is it likely to be too lose and prone to scratching/depreciation?

E) Is there anyone specific I should contact for help, or any other forums or places on line you’d suggest asking?

I thought a lot about this project a few months ago and have since forgotten some of my ideas. I will update this thread with anything that comes back to me or anything else I think of.

Thanks in advance for any and all help.

-Wine

[ps_bond]

Apologies for this going into the moderated posts - no idea why the system chose your post, but I've cleared it.

Immediate comment on your design: The top corners of the cage are going to be sharp in use, catching on everything going (including skin). I'd be inclined to radius them to make them a bit safer. The cage should give the pearl plenty of protection, but I'd want to try and fit it as closely to the pearl as possible - the easiest way to do this would be to do the ring & setting separately and then the inside of the setting can be carved (micromotor would be my weapon of choice) to fit (easiest while it's still a wax). It'd also allow for cleaning up the inside of the setting post-casting... The would then need joining back onto the shank post-casting - given it'd have the pearl inside it, I'd laser weld it on (ask around jewellers - or jewelers near you).

As far as the casting goes - propane will melt it, but oxy-fuel will be faster. 90% silver should be fine if you're set on only using the coins. Crucibles - an open scorifier rather than a traditional cupped crucible is easier with flame melting. What are you casting into? Sand casting needs a lot more metal for the hydrostatic pressure, so has massive sprues in comparison with vacuum or centrifugal casting. Do you have a kiln for burnout? Would outsourcing the casting process be wise, or are you wedded to the idea of casting it yourself too?

[Dennis]

The main problem I see, is that the pearl which is a delicate thing, will be visually overwhelmed by your engineered mount.

After all, it is intended as a gift for a woman, not an embellishment for a motor car.

As such, I would construct a basic ring, with an unobtrusive mount, solder on some wires as claws, or even just glue the pearl into a protective hollow shape.

Some intensive browsing of rings online will give you more jewellery-like ideas.

My example below shows an example for mounting and protecting a fragment of irregular safety glass. Dennis.

[pearlescence]

I think it is a very over complicated way to get around setting the pearl. far easier to get it half drilled and set it on a post - secure and you will be able to see it as well. Pearls are moderately tough, though you should not think about wearing a pearl ring every day. No dish washing etc.
That being said, congratulations on retrieving the pearl and planning such a gift.
Make sure whoever drills it has the proper kit and skills.

[josef1]

I like the design I would cast the ring and head separate but put holes in the shank that are countersunk underneath then have locating pins on the head that can be riveted over once the pearl is inside. It would also be easier to clean and polish in 2 parts aswell

[Tabby66]

I like that method Josef. The only thing I would change is having less weight in the head, so that the pearl is more visible.