Making a Three Stone Diamond Engagement Ring.

First up, this is not going to be cheap. It will cost you the same, or more than, the cost of buying a similar ring in a shop. But, your ring will be unique, and special. And, as an added bonus, if you factor the cost of equipment into the cost of the ring, she gets a sparkly ring and you get a box of wicked tools. Win, win (so long as she says "Yes!").

So, I know the thing most of you want to know is "How much does a project like this cost from scratch to finish?" Well if I said the average wage of an American is $30,000 then this project cost less than a months wage.

I make significantly less than average so it was a good deal more than a months wage for me... I know, I know, you can hear someone playing the world's smallest violin.

Any ways, supplies. Here's a list of the tools I bought. You probably don't need all of this stuff, but I didn't really feel like going half-arsed on this one, so I bought the right tools for the job.

The two suppliers I used were http://www.contenti.com and http://www.fdjtool.com

Reference Books:
Modeling in Wax for Jewelry and Sculpture, Lawrence Kallenberg
Jewelry Wax Modeling, Adolfo Mattiello

Equipment:
Bench:
Work bench (made from some free wood from ikea),
Bench Pin
Bench Vise

Magnifying Visor

Measuring and Marking:
Carbide scriber
Degree Gauge
3" Scribing Dividers
Vernier Callipers
Ruler
Ring mandrel

Sawing:
Jewlers saw frame
Saw blades 1/0, 2/0, 3/0
Fine spiral saw blades

Filing:
Wax needle file set
Standard needle file set
Large flat wax file
Double ended half circular wax file
Fine round needle file

Drilling/cutting:
Spiral Drill or Pin Vise
Drill bits, 0.8mm, 1mm, 1.3mm, 1.7mm
Fine wax detaliers
Exacto knife

Wax shaping:
Wax carving tools
Alcohol Lamp and denatured alcohol as fuel.
Cordless wax pen
Ring tube sizer

Flex shaft:
Flexshaft motor
#30 Handpiece
Wax burs
Wax detail burs
Wolf Tools wax trimmer
Cylinder bur 11.1mm
Jiffy Jig

Wax:
Wax wire assortment
Wax tablet assortment
Wax ring tube assortment

Diamonds are a girl's best friend... they are also De Beers best source of income.
The way in which De Beers controls the pricing of diamonds is frankly absurd, and add to that the exploitative manner in which some diamonds are mined and you're left wondering why the hell anyone wants a diamond in the first place. The answer, of course, is that they are simply amazing to look at.

So, how do you get real diamonds without the ludicrous cost, and ethical ambiguity?

You should start by giving Apollo Diamonds a call. They make them significantly cheaper than nature does.

I like to think Apollo do it through some sort of giant Rube Goldberg'esque machine in a wooden shed, but I've been reliably informed that it is slightly more scientific than that, involving big metal machines and, most likely, magic. You can read more about the process they use in this article.

The diamonds Apollo create are identical in all respects to the ones formed naturally. Same, hardness, same chemical composition, same refractive index, everything. They are not substitutes like Cubic Zirconia or Mossanite, they are real diamonds, without the nasty mining process.

Apollo create white diamonds, I got two 0.21ct VS2 F diamonds, 4.5mm x 3mm emerald cut from them.

The process they use is slow, and creating large diamonds is tricky and expensive, so most of the created diamonds they offer are less than 0.5ct. Which suited me fine as I only wanted two side stones. Apollo have limited inventory, but do sell loose stones to the public.

Ideally I wanted the center stone to be a Paraíba Tourmaline (an extremely beautiful, and rare, turquoise/teal colored gemstone which is often more expensive than diamond due to the fact that there is only one 'true' source for them in Paraíba Brazil). Needless to say I can't afford such a natural stone.

But, that's where mankind steps in to save the day again. Chatham Gemstones create all manner of gemstones in their labs, and sell loose stones to authorized dealers (or any one with a credit account).
After talking with a dealer she found me an experimental lab created garnet (which they no longer produce) which has the same color as the Paraíba Tourmaline and the hardness of a garnet (7.5) making it ideal for setting in a ring.

I bought a 1.3ct VS Pariba Tourmaline colored garnet, 7x5mm emerald cut from them.

One of the most crucial steps in this process is laying out an accurate design before you even start carving the wax ring.

I used illustrator to layout my design, but a good old fashioned pencil and paper will suffice.
Be sure to draw your designs to scale and with accuracy.

Before I started the design I did a bit of research on typical ring dimensions and designs.

Try not to make wall sections thinner than 1.3mm for casting.
Bear in mind the finished weight of the ring, don't make it too thick or it will cost a fortune to cast. Also, plan out the areas you are hollowing out (to lighten the weight) in your design, don't leave them as an after thought.

Use a typical referenced orthogonal view (front, top, side) to work out all dimensions of your ring.
Use the size of your girlfriends finger as the starting reference for the drawing and the sizes of your stones as the scaling for the prongs and seats.

The easiest way to make a ring blank (the starting point for carving your ring) is to use a wax ring tube. Matt Wax make ring tubes in three different wax hardnesses:

Blue - Soft, flexible
Red/Purple - Medium, flexible.
Green - Hard, strong.

I used a 1 1/8" diameter flat top purple ring tube.

Referencing your drawing, use the pair of scribers to draw a line around the whole of the tube measuring 1mm wider than the maximum width of your ring (the 1mm extra is a safety margin for filing and sanding.)

Using the jewlers saw and a fine spiral saw blade cut your rough blank free from the tube.

Cut 0.5mm further out from the scribed line, keeping the line on the inside of the blank (this gives you a margin to file off the worst of the saw marks). Don't try and cut straight through the tube all in one go, instead work your way around the tube paying careful attention to the location of the scribed line.

An easy way to cut a truly square ring blank is to use a mitre box and saw.

Once you've cut your blank free, use the larger flat file to remove the worst of the saw marks.
Then use the ring sizer to scrape the inside hole to the desired finger size. Keep the hole about 1mm smaller than the finished size to allow for shaping and sanding.

Using the flat wax file, and some sandpaper (600 grit) smooth the cut surface of the blank.

Referencing your drawing, use the scribes and the edge of the flat top to mark 1mm higher than the tallest part of your ring all the way around.

Use the inside of the finger hole as a guide to scribe 1mm wider than the maximum width of the ring shank on both faces of the blank.

Scribe out the rest of the rings dimensions using the ruler and carbide scribe on both faces.

To get symmetry on the top 'arc' of the ring, from the shank to the head, use a cardboard (note card) template and simply reverse it for the opposite side.

Rub talcum powder into the scribed lines to make them visible.
Don't scribe your lines too deep, or they may be hard to polish out later.

The blank should now resemble the photo below.

Alternatively you can use one of Matt Waxes ring templates to block out your design

Set up the flex shaft,clamp, trimmer and bur as in the photo.

Use the bur to shape the blank to the proportions of the ring you scribed.
Run the flex shaft fairly fast to remove larger sections of wax, and reduce the speed as you move closer to your lines.

Leave the scribed lines inside of the cut to allow you to file accurately up to them.
Don't try to get to the 'finished' shape using just the trimmer, what you are doing in this step is getting the ring blank to a point at which you can refine it with files and sandpaper.

Find the midpoint of your shaped ring using a ruler and the dividing scribes.
Mark the center point all the way around the band, and mark the cross center point of the flat top.

Using the center lines and your drawing as a reference, block out the areas for the stone seats and the width of the final ring shank.

Use the saw with a 3/0 blade to cut lines to define the areas for the stone seats.

Use a flat escapement needle file to cut down the stone seats to 0.5mm bigger than their final heights and widths.

Using your stones as a guide, scribe the size of the stones' seat holes into the top of the blocked out platforms on the ring. You can use the Matt Wax templates to help this process.

The stone should sit in the seat to the depth of the last facet before the girdle of the stone. This will allow it to have a solid base with good light transmission.

Use the pin vise to drill a center hole through the seat, and use a sharp flat wax working tool or graver to cut the square hole. At this point you can either cut all the way through the ring, or cut the seats to a depth of 1.5mm (as the following step will open them all the way through).

Use a sharp wax working tool or graver to slightly bevel the edges of the seat holes.
Keep the walls of the seats 1.2mm thick or more. Use the degree gauge to measure the wall thickness.

The object of this process is to lighten the weight of the ring by cutting a channel underneath the stone seats thus hollowing down the thickness of the top of the ring.
It is one of the hardest parts of this project so take your time.

You should aim to thin the side walls to no less than 1.2mm, and the top depth to no less than 2mm.

Turn the ring so that the top of the seats face downwards and using the scribes trace a 1.2mm wall around the inside of the ring underneath them.

Use the flexshaft with the detailer's burs to carefully cut the channel between the scribed lines.
Tidy the channel using sharp edged shaped and curved wax working tools.

Use the degree gauge to measure the thickness of the walls, and hold the piece up to the light to check for uniform thickness (the lighter the areas the thinner the wax).

Feather the channel out to the mid point of the ring band to give a smooth transition into the rest of the band.

Use 600 and 1200 grit wet dry sandpaper to shape the ring to the correct dimensions, bevel the shank edges, and to remove all of the file marks from the surface.

The purpose of cutting 'balconies' into the stone seats is to increase the light transmission through the ring (and stone), to add elegance, and again to lighten the weight of the ring.

This step is very hard to do, so take your time.

Use the scribe to mark the location of the balconies on the ring seats.
The areas above and below the balcony windows should not be thinner than about 1.5mm - 2mm.

Drill a center hole from both sides of the ring for each balcony window. Do not drill straight through, it is too easy to drill out in the wrong place.

Thread your saw blade (3/0) through the two center holes of one balcony. Rest the ring in your left hand and your fingers on the bench pin. Using a just a small section of the saw's length (about 1/4") rock the saw so as to cut only the window closest to you, leaving the hole on the reverse of the ring uncut. Think of the cutting motion as a pivoting one, where only the top of the saw moves around cutting the window (along the X, Z axis) and the base remains fixed in the drill hole on the reverse side. Cut inside of your scribed lines, then remove the saw and blade, and finish the window using a sharp wax working tool or graver.

Turn the ring over and repeat the cutting process for the window opposite to the one you just finished.

Continue like this until you have cut all six windows for your balconies.

Use the fine circular needle file to cut the channels for the prongs to sit in.

Depending on the thickness of the wax wire you are using for the prongs use the appropriate section of the file to cut the channels.

For the center stone seat, it is a good idea to flatten off the square edges (to create a octagonal oblong) before attempting to cut the channels for the prongs. This will stop the file slipping and make it easier to locate the channels properly.

In order to get a good cast from wax, you need to polish away all tool marks and leave the ring with a shiny surface.

Start by using 600 grit sandpaper to remove any remaining file marks or scribed lines.

Use 1200 grit sandpaper to smooth the paper marks away, and create a satin finish on the ring.

Finally use a nylon stocking (pantyhose.. whatever) to polish the ring and remove any last imperfections and bring out a shine on the surface. To polish the insides of the windows and stone seats I cut a thin ribbon of stocking and attached on end to my bench pin, I then threaded the other end through the holes in the ring and rubbed the ring along the threaded ribbon.

You can also use a product called wax gloss to slightly melt the wax surface and remove imperfections. Use it sparingly and polish with nylon stocking. Wash the ring in water after using wax gloss so as not to soften the wax further.

Alternatively, if you have mad wax working skills you can use an open flame to 'shine' (melt) the surface of the ring. It is very easy to melt and ruin a piece of work using the open flame method and I wouldn't advise it.

Once you have polished your ring, add the prongs.

I used blue and green wax wire for the prongs.
Make them a little thicker than you anticipate as their size will be reduced in the tumbling and finishing stage of the casting process. Also cut them long (1mm - 1.5 mm) longer than needed, it is easy to file them down once cast in metal, but adding more height to them is a little trickier.

For the smaller stones prongs I use 16 gauge wire, and the larger I used 14 gauge wire.

To attach the prongs use a toothpick coated with a small amount of cyanoacrylate (super glue) to line the channels with the glue. Then position the prong in place and hold until it sets.

Don't use too much glue as it will spill out of the channel and you will have to clean it off, and that is a real pain.

To hold the prong in position permanently you need to 'spot weld' it.

Do this by twisting a fine copper wire (a single thread from an standard electrical cable will do) around the nib of the cordless wax pen.Bend the twisted wire at a right angle, so that the deepest it can penetrate is less than the thickness of the stone seats' wall and the prong attached to it.

Use the wax pen to heat the wire and weld the prongs in place by pushing the wire through the inside wall of the stone seat through into the prongs.

O.k, so while I might have the nerve to try and carve a wax ring, I don't have the skills or resources to cast metal.

So, I did a little looking around and found a local trade Jeweler/Supplier/Instructor who could do the tricky casting, finishing and stone setting for me.

It cost me a little bit of a premium to have someone do all these steps, but it is probably worth it.
I used The Jewelers Warehouse in Silver Spring, MD.

I recommend taking a look at this great instructable on the lost wax casting process, which shows the process in detail.

Or'' take a look at this video:



Briefly the casting process happens as follows:

The ring is prepared for investing. Investing simply means to surround the wax with a hard substance, in which it will leave a hollow behind when melted. This then becomes the mold for casting the metal ring.

Before investing the ring a wax sprue, and button, is added to it.
The sprue is a thick wax wire which is attached to the base of the ring band, which will form the pipe for the metal to be poured into. The button is a wider piece of wax on the opposite end of the sprue which will form the basin to pour the molten metal in.

The button (with sprue and ring attached) is placed on a rubber diaphragm base, and a flask is attached to the base.

Investing media is mixed as a liquid and poured into the flask around the ring.

The flask is then placed on a vacuum table and the bubbles forced out of the investment media, as it is left to set.

Once the investment is set the rubber base is removed, and the flask is placed upside down in a burn out oven. This burns/melts out the wax from the investment. The wax ring is 'lost' during this process, leaving only a perfect hollow of itself in the investment, hence the name "lost wax casting".

The investment is then heated in the oven to a specific temperature. When it is hot enough it is placed in a centrifuge powered by a large spring. The metal of choice is then melted in a crucible next to the investment and the centrifuge released, pushing the liquid metal into all the hollows of the investment mold. Sometimes the centrifuge is skipped and the molten metal is poured into the mold on a vacuum table instead.

Once the metal has cooled very briefly the still hot investment is quenched in water causing it to fracture away from the metal. The remaining investment is either broken away using brushing, concussion/vibration, or dissolved away using chemicals. After which you are left with a metal cast of the original wax ring.

There are a number of steps to finish a white gold ring.

The first is to clean up any surface or casting imperfections. This is usually done manually using grit paper, sanding wheels, buffs and rough buffing compounds.

See this video for a basic walk through of the main techniques:


These days many jewelers also use a tumbling process to burnish the gold to make it highly reflective.
The process of burnishing basically requires a harder metal to be rubbed against a softer one to flatten/burnish the surface imperfections and create a shine. Tumblers use pellets or tiny rods of hard metals loose inside to burnish the gold jewelry, because of this, tumbling is often used to burnish areas not easily reachable with traditional methods. However the process is fairly aggressive so is not suitable for more delicate works.

14K and 18K white gold contain high levels of gold which is yellow (between 50%-80%). In order to keep the gold 'white' 14K and 18K white gold jewelry is often Rhodium plated. This increases the hardness of the surface and also masks the yellow gold color.

So, after basic finishing and tumbling, the ring was Rhodium plated and then buffed to a high shine.

Stone setting is an art form, there are numerous books devoted solely to the process, but the basics are as follows.

First the prongs of the setting are cut down to the correct length, usually 0.5mm - 1mm higher than the desired height of the set stone (depending on the stone's size).

Then v-shaped grooves are cut on the insides of the prongs, using a bur, at the height at which the girdle of the stone should sit in the seat.

The stones are then pushed into the seat and 'clip' into the grooves. The base of the stone should rest firmly in the hole in the seat, and the girdle should rest in the grooves.

The setter then uses a burnisher/pusher or modified graver to push the top of the prong over the stone.

He then shapes the top of the pushed over prong (usually to a round shape) using a bur or file, and polishes them.

See here or here for more detailed information on prong setting.

The finished ring.

Cast in white gold and set with the stones.

Taking a hot air balloon ride tomorrow morning.... so chances are she'll either say yes, or throw me from the basket.

I'll let you know afterward... wish me luck!!


EDIT:

She said yes!!
(Well actually she kind of cried and nodded.... but the effect was the same).


Yay!