Making a custom Platinum Diamond engagement ring

Step 10 A ring is finished.

The wax model is then sent off to the platinum caster.

Whilst I cast my own gold and silver items, platinum casting requires some very specialist equipment. So the wax is used in the "lost wax casting process" and the platinum ring is returned.

I then clean up the cast piece, I file, sand and polish it and set the diamond.

Here is the finished item.

Comments

[byudzai]

The step I would love more info on is carving the hole for the stone. I've tried doing this and found it near impossible to carve a hole just the right size and which held the stone well underneath. Do you melt the wax and press the stone in?

[geekman101]

why do you have to make another wax ring? wouldn't you just give the platnium guy the original? cause then you wouldn't have to make a mold?

[jillybishop]

what tools do you use to carve the wax? I find it very difficult to get sharp detail, although, as I've only just started casting, that's probably not surprising.

[airgun]

try brassknuckels or a sieries of rings to make tht desing just helping sincerlyyour friend -Bammmy boy

[luch]

Very cool! I would love to some pictures of the tools that you use! Would you be able to post some?

[Vlorbschnat]

What platinum casting house did you use?

[Kookie007]

Wow this looks really professional!

[triggernum5]

Perhaps because he is a professional..:) Only critcism I have on this is why opt to write up a Pt casting that you can't show the ENTIRE process for, when he does actually cast easier to work with metals himself.. I'm curious how the wax gets lost.. Is it instantaneously vapourized? I always assumed they used some kind of powder-mould more like the wax template..

[chrisparry]

Hi The wax melts at about 70 deg c. The flask witht he wax in is put in a kiln for a couple of hours which helps to cure the mould and at the same time burn the wax out. It just melts away to nothing.

[liny]

wasnt wax melting point 54 deg celsius? Or is it a special type of wax.

[triggernum5]

So it must be vaporized? If it just melts, then the wax would occupy the more than the same volume in liquid state.. I'm unclear how the casting works, ie: what nore heat resistant substance does the wax mold displace to accept the platinum? Or is it silica-like, and can drain liquid wax?

[chrisparry]

The steps of making covering the wax in investment (which you cast into) is not shown. That alone is its very own instructable A google search on "the lost wax casting method" would answer all the questions that you have. It is quite a detailed process.

[smurfsahoy]

If you're casting a huge item by lost wax (like a statue), you might have multiple connections to the outside air (vents in addition to the sprue), and you might even melt the wax out/fire the mould (if you use clay) upside down so it drains out, since evaporation would take much longer, then flip it over and cast the metal.

[mattbeddow]

in most lost wax methods the wax piece is coated in a liquid clay called slip, then harder clay to make a block. This is the fired in a kilm like pottery and the wax melts and evapourates out of a hole left in the clay to pour the metal in. The molten metal is then poured in and allowed to cool slowly over 24 hours or so, depending on the size and metal used. Once cool the clay is broken up using ultrasonic sound waves (like how a kidney stone is broken up) to extract the cast metal. A new clay mould needs to be made each time but the clay can sometimes be reused (depends on the type of clay) hope this helps!

[GunsAndGloryFx]

No less than *Gorgeous*. I love seeing the progression from wax blank to prototype. Thank you for posting this. Any chance we'll see your centrifuge process on a future instructable? Also, from where do you purchase your supplies? Again, thanks. Excellent work.

[Radiant Creator]

agreed very nice

[struckbyanarrow]

wanna know whats gorgeous kittens, baby kittens

[benthekahn]

Thats redundant.

[struckbyanarrow]

hehehe redundant i got to start saying that but first i must look for a dictionary!

[bowmaster]

There is no such thing as "baby kittens".

[struckbyanarrow]

...

[chrisparry]

lol

[bowmaster]

Unless you count cat embryos

[HammyHavoc]

Those are feline embryos. Baby kittens [: *Smug look* Owned. Great instructable, really fascinating to look at the whole process!

[Pancakeslayer]

LOL, my cat just hatched out sum cat embyos

[chrisparry]

Supplies come from many sources but the biggest jewellery wholesaler in the UK is probably Cookson Precious Metals and in the USA is probably Rio Grande. I would love to do some more instructables, so if time permits, I will do some more detailed projects.

[dewexdewex]

Chris, have you tried using rapid prototyping machines for your models? The machines which use laser sintered powder produce extremely hi resolution/definition pieces which may even be suitable for loss wax directly. I fully understand if this comment annoys you: these machines are killing hand craft. Regards.

[chrisparry]

hi I actually use CAD/RPT in my work where and when it is required. I just use it as another tool at my disposal. Sometimes I will opt for making a ring directly from bullion, sometimes in wax, and sometimes via a CADRPT process. I simply choose the method which will give the desired effect. nothing wrong with technology, afterall a purist would argue that the lathe has no place in a jewellers workshop..........They are all just tools and it is how you use them that is important.

[soul_jahz_united]

and you posted this here so we could make what exactly?

[Patrik]

Something like this, for example? Or maybe like this?

Personally, I think it is absolutely fascinating when a real professional shows how they work in this amount of detail. And just because this is really high quality doesn't mean we poor shmucks can't learn something from it!

You're not going to be making a platinum engagement ring on your first try, but wax carving is not that hard, and making an RTV mould is fairly straightforward as well. Getting a top quality product is hard - but doing a fun weekend DIY project could be within reach even for beginners...

[samando]

Where would you get the rubber used in the mould in Australia

[chrisparry]

Hi A model making shop, or try ebay. you are after a 2 part RTV silicone rubber. In most cases the hardener is added in a 20:1 ratio. I just use some sensitive scales to get the ratio correct each time. Try searching on feebay for the mould if there is nobody in town. A mould the size above costs about UK £1 ish to make. I typically buy 2.5kg at a time, which is enough for about 30 moulds of this size. The silicone rubber does have a 6 month ish shelf life, if not used.

[samando]

Thanks, i won't try this just yet, as i am a kid, but i may try it when i'm older

[agthomas]

Beautiful! I know it's not easy... I have always wondered about prong settings. If there is room to put the stone in, what keeps it from coming out?

[chrisparry]

The easiest way to explain it. Make an upside down claw wiht you hand (palm facing upwards) and drop and apple in. very lightly grip the apple so that you can pull the apple out and put it back in, so that it is a snug fit. That is how the model above was prepared. The prongs are so tight that the diamond can go in and out but very snuggly. Now with the apple back in your hand, bend over the top knuckle only on each finger. The apple can't come out again, as this was the only way in, and the fingers (prongs)have now been bent over the top of the diamond to stop it coming out. This is done so that their is NIL movement on the diamond and it is set securely. The tips of each prong are now filed, sanded and polished. The crtical point here, being that they do not stick up and are easily snagged on something. A prong that is easily snagged, can easily be bent backwards and there goes your diamond. The metal thickness of these prongs bent over the diamond is typically 0.5mm - 1.0mm thick. obviously the larger a diamond is, the more or bigger the prongs have to be.

[aglaranna]

The prongs are pushed down over the stone after you place the stone in the setting.

[laernmoer]

Thank you for sharing this. I like that someone is willing to show the world how they do their craft. I think the internet is great for sharing information. My mother's boyfriend is a jeweler, and I can never see him showing people on the internet this. He's showed me, but I don't think he'd want to take the time to show everyone! This is useful for casting ideas for other small items, not just jewelery.

[commiechink]

i've done some lost foam aluminum casting in college which is very similar. This instructable is a really good primer on how it's done, but probably not something that you'd want to use as your only instructions for doing a casting... especially with metal as expensive as platinum. On the flip side, this is a PERFECT instructable for learning the basics of how a ring is made. I had already learned this info when i designed my wife's ring and it was useful in working with a custom shop to provide them better instruction when they made a wax form from my designs. anyway, chris, thanks for the nice instructable!

[danielmilhousechun]

wow i made a lot of rings using the lost wax method in highschool. I eventually want to make the ring i propose with. so you outsource your platinum casting? Thats a good idea what do you need to send them? just the wax model? or a mold also?

[chrisparry]

Good luck with making your own ring. You can of course outsource most of the steps above. There are professionals that only carve waxes, or make moulds, or cast, or polish or set. so you could take on a foreman type roll and just outsource as many aspects , that you can't do yourself. There is one thing to consider. Finishing platinum to a high polish, is not as easy as just saniding and polishing something like silver. It is very time consuming to get the metal down to a high polish finish. again, that process of polishing alone, is worthy of an Instructable.