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redportleft
10-01-2005, 10:13 PM
Hello. Can any one tell me anything about casting gold using cuttlefish bone as the mold medium and the throwing method of casting the ring. Links to related sites would be very welcome. :D

Many thanks Edd.

Lou
10-02-2005, 07:36 PM
I've cast silver with cuttlefish bone before. It gives better results with silver from what I've been told and read. When I make a mold with it, I cut it in half, soak it in water, then press my pattern into one side of the mold and then put the other half on and press down (a vice is very nice for pressing them together). I carefully move them apart, pry out the pattern, and cut in the sprue with a sharp scapel. After you have everything as you like, close the mold (I usually use wire and wrap it together very tightly). Let it dry a few days.

Jeff Mack
10-03-2005, 07:34 PM
Just out of curiousity, as your title mentions ancient casting, what era are your trying to replicate? I've done several different methods of casting using technology available in 600-1600 AD Europe, and I've got some references outside that era.

Jeff

redportleft
10-24-2005, 07:21 PM
Hi Jeff. Sorry It took me so long to get back to you. Just so It doesn't get all confusing for me I would like to explain that this topic is on behalf of a friend of mine. Who lives 400 miles away from me (wonder why) and doesn't bother with computers as yet.
He saw my smelting setup and asked me if there was anybody out there in $2 crucible land who could help him with his ambition to cast a gold ring in an older way than used nowadays. Now to make this more interesting, The gold is Welsh gold. Paned and dug and sucked from a river by him self, over the past 4 or five years. Hard work. Hard to find.
Having amassed several ounce's in nuggets and dust its come time to think about making the two rings for himself and his girlfriend. But has so far been unable to find any books or people who can educate him on any of the older ways of casting gold and throwing it by hand. (I think that's what he called it, centrifugal casting technique done by hand) So any help would be good.
The chap in question is called Edd and I'm Tom. Many thanks.

Techno
10-24-2005, 07:40 PM
Since gold is such a soft metal you can beat it into shape easily. I imagine that casting wouldn't be used much for gold when it works so easily.
My brother drilled a hole in a lump and formed into a ring using a spoon as the hammer and a tapered punch for the hole.
Later he tried the same method with platinum but it didn't work. Anvil and sledge hammer too.

Lou
10-24-2005, 07:55 PM
Hm, was the platinum native (as in a nugget)? If not, chances are, it was Pt/Ir10 and that's why it didn't bend. Iridium is a very hard metal and it is added to platinum to improve hardness. He probably contaminated it with iron while attempting to forge it; that's easy enough to remedy: boil in HCl (dissolve iron but not platinum). Pure platinum is somewhat malleable and is not easily cast without using induction and specially designed equipment (narrow range of liquidus). Gold is the most malleable of metals and cold forging is easy to do, however, greater dimensional accuracy can be achieved via casting because it is a dense, fluid metal. That's why people can get such nice ornamental rings.

T-Gold
10-25-2005, 10:48 AM
Techno, hard to forge a bunch of flake to shape.

Sling casting is still done by reenactors and the desperate... not particularly complex. Your friend needs to hit his local bookstore and buy a few decent jewelrymaking books after perusing them to make sure they contain the relevant info.

redportleft
10-25-2005, 06:18 PM
Hello T Gold. Edd has done allot of searching for books on the subject and not come up with what he wants. Any pointers towards new material would be gratefully received.
The older crafts required allot of skill because of the lack of modern equipment and learning about these skills and understanding them is a joy in itself and having learnt to find and get the gold the hard way (and it is not common in Wales and worth allot more than your average gold as a result) He wants to carry the process on through, with traditional methods :-) (Mad fool)

Ta Tom.

T-Gold
10-25-2005, 10:05 PM
This may be true of some old processes, but not of sling casting. If you can tie a piece of rope to a quarter full gallon bucket and whirl it around without water dripping out you can sling cast. If he can't find info, he either lives in BFE or hasn't looked very hard... all the same I'll try and find something you guys can use.

redportleft
10-26-2005, 05:09 AM
Many thanks for your time.

Tom

Techno
10-26-2005, 07:52 PM
This is getting a bit off topic but the method he used with both hammer methods was to melt the metal into a lump. Neither one was in lump form to begin with.
As I understand it platinum is a hard metal to begin with if something is alloyed to make it harder....He ended up taking the lump of platinum to a jeweler and cashing it in. Worth quite a bit!
It began life as a 9" square sheet less than paper thickness his workplace was going to throw away.

Lou
10-26-2005, 07:56 PM
Very hard indeed and if I may inquire, what did he melt it with? Bet he got a good price for it huh techno?


Obtw, it's easy to place your flask or mold into a small bucket filled with sand and then cast and give it the centrifugal treatment. How thick is this ring anyways? Chances are, the gold will exert enough pressure to fill every cavity in the mold just from gravity.


Lou

redportleft
10-26-2005, 08:50 PM
Hi lou, It will be a heavy plain ring but its the whole craft thing thats important to Edd. The old boys didnt have www. science.com and still managed things we find hard to do today. The man who swings an axe has to know more about the tree than the man with a chainsaw. Not to mention the physical skill. Less is more..............

:wink: Tom

Lou
10-26-2005, 09:34 PM
I know what you mean. When I first did lost wax it was all very crude but I've since progressed. No, you don't need "science.com" to do what the old boys did, but I'll tell you this much, any chemist (or alchemist) living hundreds of years ago would love to have a forum where they can discuss their findings, criticize others' techniques etc. Progress is not a bad thing.

Since you and your friend are hell bent on ensuring it be done "ye olde" style, then I hope this link may prove informative.

http://www.frojel.com/Documents/Document02.html

Good luck.

redportleft
10-27-2005, 05:30 AM
Many thanks Lou. Had another hunt around my self today and got lucky,
http://artisans.ombra.net/tecniche/CUTTLEBONE.htm :D
Now I just need to find someone who has some hands on knowledge.
Might have a go my self.

jtobako
10-27-2005, 05:25 PM
lou? it was called mail (no e)? maybe you have heard of it? paper and ink, envelope, stamp, even sealing wax?

lot of those letters still around. how many forums have dissapeared?

not a luddite
john tobako

Lou
10-30-2005, 11:30 PM
True, but how many of them liked waiting 4-6 weeks for their post to arrive? Not to mention, they didn't have xerox back then...so you'd have to make a copy of your letter to each fellow experimenter you want to send it to. Not fun. Next time think it through :)

redportleft
10-31-2005, 05:31 AM
And it only took you four days to reply LOL.

Now,What about the hand throwing of gold? eh.

Have I got to surf the net my self or what? :D

joe
11-08-2005, 03:15 PM
As a side point in gold casting I was wondering how did they do in the Bible when they cast a gold bull or whatever in 2000BC. They were in the desert, they had no crucibles, no propane, no coke, no parting dust etc etc. How on earth did they do it???? At that temp of melting gold???

Techno
11-08-2005, 08:13 PM
They build a frame from something maybe wood. Then they hammer the gold out onto the frame and they have a golden bull.

I think the collosus of rhodes was made up in parts more like the statue of liberty. Imagine casting something of this size in one shot!

Tim
11-08-2005, 08:14 PM
There hasn't been an ancient civilization worth its salt that didn't have pottery. With care, a water jug is no different from a crucible...

Tim

Cyrus
11-08-2005, 11:28 PM
While the Temple had plenty of gold, the bronze "sea" was... bronze.

~

" The bronze from the two pillars, the Sea and the twelve bronze bulls under it, and the movable stands, which King Solomon had made for the temple of the LORD, was more than could be weighed."

(Jeremiah 52:20, NIV)


I've also wondered about how it was cast... it wasn't a gold leaf bowl, it was a big thick heavy bronze one. Sure they had crucibles, as Tim mentioned. Crucibles are basically clay pots without the art of ceramics, just the utility of ceramics. :lol:

It must have been quite a casting session! We think of people long ago as "dumb", but they could do some amazing things...

Cyrus

joe
11-09-2005, 12:34 PM
Hi you guys ever heard of Cellini casting his Perseus larger than life in bronze in one single shot? His autobiography is a MUST for all bronze casters. It makes wonderful reading and can be downloaded too free! :idea: