A brief PS on this subject...
I've just ordered a copy of Mark Grimwade's book mentioned here - thanks for the recommendation, Peter, I looking forward to reading it. And I heard back eventually from an expert on Argentium, to whom I sent a question, to say that precipitation hardening should not result in greater brittleness than work hardening. The issue of brittleness does arise with Argentium when it is actually at high temperature, so when red hot it should not be moved or quenched or it may crack - the advice when annealing is to wait for the glow to go out of the metal before quenching.
Alan
I've been reading this thread with interest, especially as I only just noticed that Cooksons are now selling Argentium.
Personally I wouldn't quench any metal that I work with now, and much prefer placing work on a steel block to cool it down. As you say, a quick search on the internet shows that Argentium needs to be supported to prevent sag, anneals when its an orange glow colour / wet looking, and shouldm't be touched whilst hot for fear of brittleness and cracks.
Going to buy some to see what its like to work with. As it doesnt develop firescale, I presume it polishes up to a brighter finish than regular silver?
Also does anyone who regularly works with Argentium recommend a specific type of flux or solder that Cookson sells?
The only bit so far that baffles me a little, is fabricating with Argentium. With regulard sterling / fine / reflection silvers I can have a piece with many different solder joints on it no problem, as you do when making something a bit more complex.
But with Argentium does this start to become tricky or would you simply approach several solder joints in the same way? Or would you forget the solder and just concentrate the flame on each specific joint in order to fuse them?
Thanks and apologies for asking some fundamental questions, but it looks like an interesting alloy to work with.
Nick
Cooksons only sell the 935 grade - if you want 960 try http://www.alliedgoldltd.com/
I do quench, as I think you get a slightly softer anneal, but I'm cautious - after torching I turn all the lights out, wait for the glow to fade and I don't have any cracking problems.
Yes, you can finish Argentium (both grades) to both a harder state and brighter polish than traditional sterling. We've already talked about precipitation hardening here. Further finishing to develop maximum tarnish resistance requires careful cleaning and a longer, lower temperature heat treatment - some useful points in this discussion: http://argentium-guild-forum.2304831...td4383053.html
You can solder Argentium much like sterling (though the tendency to sag or crack at high temperatures may require a slightly different approach, depending on the piece) and Cooksons sell a range of Argentium solders from easy to extra hard. They also sell a flux specifically for use with Argentium, which looks and behaves like Auflux - http://www.cooksongold.com/Jewellery...rcode-997-6425 - I've been using both successfully for fusing, just brushing a little over the joint area itself. It seems to help the metal to flow, but because you don't get firescale you don't have to worry about shielding other parts from exposure to the flame. If you have accurate heat control with a suitable torch (I use a Smith) you can do virtually all joins by direct fusing without solder, but it takes some practice to recognise the fusing point so not over-do or under-do it. Argentium does not conduct heat as fast as sterling, so it's easier to concentrate the heat on the joint area itself.
Alan
Just to add a couple of points to this discussion.
First, re annealing, I had an excellent discussion on the phone recently with the inventor of Argentium, Peter Johns. It was mainly about furnace annealing 960 tubing (of which I've obtained quite a large quantity mainly for putting cores in glass and silver beads) but we ranged over other related topics. Interestingly, on the subject of torch annealing he asked how I judged temperature - and when I talked about looking for a pale red-orange glow as normally recommended with Argentium, he said you don't need to take it that hot, but to look for just the first hint of redness and then take the heat off. He reckons also that silversmiths commonly heat sterling much hotter than actually required for effective annealing.
Second, I'm now well into the book recommended by Mr Bond here - Introduction to Precious Metals: metallurgy for jewellers and silversmiths by Mark Grimwade - an excellent read for someone like me who now wishes he'd paid more attention at school in Physics and Chemistry... I did think at the time I had some deadly dull teachers, including son of Barnes-Wallace the bouncing bomb man (though I bet if I met him again now, I'd find him fascinating).
Oh, and one other thing, going back to the original topic of headpins, here are a couple of links that might be useful to someone: http://www.wiredupbeads.com/headpin_tutorial.html
http://riograndeblog.com/2011/08/mak...david-plumlee/
Alan
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