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jamesjewel
02-02-2011, 01:36 AM
:(| This is driving me crackers, its now 2.30am! I've been asked to make a piece from a fair size lump that somebody (not me) formed by melting down old pieces of jewellery made from gold of every colour and purity there is. It had been cast into a nasty looking large solid heart shape. So, melted it down formed an ingot...... well it turns out this stuff is harder than some of my hammers!
I don't seem to be able to anneal it. I know that different golds have different annealing temps and cooling regimes - quite a range. I have tried quite a few times but just do not seem able to make it workable. It's metal, it must be annealable, but I'm stumped. Any suggestions? I really would prefer to make something rather than cast it.

Polly
02-02-2011, 09:29 AM
Are you sure its just gold in there?

jamesjewel
02-02-2011, 09:45 AM
Mmm - there's a thought, but i was assured it was nothing but gold.

ps_bond
02-02-2011, 11:42 AM
Might be worth doing a Troy test on it at least. I'm having a devil of a job rebuilding a 9k wedding ring that was cut off with shears (as a result of a surfing accident) - even annealed, the thing is being very resistant to being formed round again.

Dennis
02-02-2011, 01:25 PM
Well, I would send it for scrap and offset the proceeds against new gold, which will not give you any grief. In my book that's what bullion dealers are for.

Peter, if you can get hold of a ring bender, such as Cooksons 999 718, it will bend and close any ring easily. The only precaution I take is to lay a short piece of leather strap on the moving jaws so as not to mark the outer surface of the ring.

Dennis.

jamesjewel
02-02-2011, 01:45 PM
Hi peter, have done some more research, red/rose golds seem to to be more difficult to deal with generally and I have been told there is a fair proportion of that in the mix and also green. I'm thinking of casting a much thinner ingot as a starting point, the current one is about 8mm across, and then raising the annealing temperature in the kiln 10 or 20 degrees at a time from 600. It must have a point at which the right structure will form and will also try air cooling and different quenchings. Assuming I get there in the end I will also have a repeatable method. The moral is never mix scrap! Will post outcome for the sake of anyone else who has a similar problem.
By the way, very pleased with the anticlastic stakes - not something i've done before - managed to make a fully turned over ring, have yet to set a stone in it, will post a pic sooner or later.

ps_bond
02-02-2011, 01:46 PM
Thanks Dennis - I've been malleting the thing to get the final shape true, it might be worth trying them instead - I usually only use them when I'm bending heavier stock round.

jamesjewel
02-02-2011, 01:50 PM
Hi dennis, yes I agree thats the best option but doesn't address the customers sentimentality issues. Thats why it was all put in the same pot to begin with.

Dennis
02-02-2011, 08:16 PM
Yes I guessed that, but was also concerned about the impact on you, Kind regards, Dennis.

Joe
02-02-2011, 08:58 PM
I love my ring bender from Dennis' recommendation and it has made several outings from it's drawer in recent weeks even though I've been making yet another brooch series! With a leather liner it is such a delicate tweaker of shape that it can correct tiny distortions in loads of things, even sheet!

On the annealing front, my severely limited experience has but one recommendation "quarting and parting". Let them have a sentimental connection to the gold bit and flush the silver nitrate elsewhere!

9ct is so hard! I thought I'd blunted my scorper when I tried to cut into it! It's like precious-metal granite compared to sterling! You pro's are all laughing now, I know, 'cos I hardly get a touch of low-carat gold. Get the silver out of it and it'll be a lot less truculent!

Now there's 24g of freshly annealed platinum winking at me from a crucible with a rebellious "think you're hard enough?"... my palm is blistering at the thought!

jamesjewel
18-02-2011, 08:52 AM
Well so much for that - not enough time - made a casting in the end