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Working bronze, and other metals! - Gaius Julius Caesar - 05-30-2007
Hello, as I am planning on trying out some things in the future, I was wondering if there were any clear, to the point answers to the question of annealing.
So far, I have been told when annealing iron or mild steel, to let it cool before working. Then have seen a post where the armourer was working the metal while still hot.
Which method is correct?
Also for annealing Bronze?
Do you let it cool first, or do you work it while it is hot?
Anyone be of any help here?
Re: Working bronze, and other metals! - Icelandic - 05-30-2007
I have learned from many sources to never, ever, ever work brass while hot--I'd assume the same would go for bronze.
Re: Working bronze, and other metals! - Primvs Pavlvs - 05-30-2007
Gaius,
Its the same with brass, copper, bronze etc.
Heat it till a dull red, and quench it in cold water.
Working these metals will cause them to reharden.
Re: Working bronze, and other metals! - Icelandic - 05-30-2007
Forgive me, Primvs, but I was of the understanding that you were supposed to let the brass/bronze/copper cool off on its own, and to not quench it?
Re: Working bronze, and other metals! - Primvs Pavlvs - 05-30-2007
Quote:Forgive me, Primvs, but I was of the understanding that you were supposed to let the brass/bronze/copper cool off on its own, and to not quench it?
Nope thats only for ferrous metals. Not copper alloys.
Re: Working bronze, and other metals! - Gaius Julius Caesar - 05-30-2007
So, now I've got ot ask. What happens if you work the alloys when it is hot?
And also, what about where I have seen people work iron/steel when it is hot.? :?
And, also, can you heat the bronze as often as required until you have finished thepiece?
Re: Working bronze, and other metals! - Icelandic - 05-30-2007
From what I have heard, the hot bronze will just break. So, since we usually want that in one piece, I'd suggest against it
As far as reheating the bronze, I'd believe it'd be better to err on the side of less being better, as overheating can cause it to be too soft, and therefore unusable. This, I'm not sure of, but would assume.
Re: Working bronze, and other metals! - Primvs Pavlvs - 05-30-2007
Quote:So, now I've got ot ask. What happens if you work the alloys when it is hot?
Copper alloys tend to crumble, or split when worked hot.
And also, what about where I have seen people work iron/steel when it is hot.? :?
Iron/steel is ferrous the only way to work it is hot, if you do cold it will break, split and fracture.
And, also, can you heat the bronze as often as required until you have finished thepiece? Yes you can reheat, and anneal as many times as you need. I actually suggest to do it very often.
Re: Working bronze, and other metals! - Icelandic - 05-30-2007
I think I'd take Primvs' answers over mine :wink:
Re: Working bronze, and other metals! - Gaius Julius Caesar - 05-30-2007
And also, what about where I have seen people work iron/steel when it is hot.? :?
Iron/steel is ferrous the only way to work it is hot, if you do cold it will break, split and fracture.
Now this has me confused. So why do people say to anneal iron/steel, you heat it, then let it cool, before working it? That is the answer a lot of people have given, or at least that was the way I interpreted them.
I would go with working it hot myself, as that was what I had always understood, but why do people keeping giving the other answer?
Thanks for the answers though, it has made things clearer.
As to the bronze, I would assume that no matter how often you heat it, and soften it, the working will harden it again? Does this vary according to the composition of the bronze?
Re: Working bronze, and other metals! - LUCIUS ALFENUS AVITIANUS - 05-30-2007
Gaius,
Iron and copper alloys works completely diferent. You can't work in the same way.
If you quench the iron, it hardens. It you quench the copper alloy, it softens.
If you work with iron cold, you stress the metal and finally it brokes. If you work with copper alloy hot, you stres it and finally brokes.
Silver and gold are, less or more, similar than copper alloys. But a lot more easy to work!
Re: Working bronze, and other metals! - Gaius Julius Caesar - 05-30-2007
Thanks for your help folks.....
So, annealing iron means what then? The same as annealing mild steel/steel?
Re: Working bronze, and other metals! - Robert - 05-30-2007
OK, I asked my neighbor, a gifted metallurgist and he gave me a lengthy explanation which I will try to compress in a few sentences.
Copper and its alloys have a crystalline structure and heating destresses the metal by allowing the atoms to rearrange themselves in a more linear form. This causes the metal to stop resisting a change in shape through bending or hammering. However, changing the shape causes the atoms to again become stressed and the metal hardens when worked. So anneal, when the working gets tougher, stop and anneal again. Working it hot wrecks havoc on the crystalline structure and it shatters (trust me, I tried!).
Iron is a much harder metal (it will cut copper) and has a totally different atomic structure. Heating it sufficiently makes the metal more plastic by allowing room for the atoms to shift in respect to one another when force is applied. This is why iron and its alloys are worked very hot.
Enjoy!
Re: Working bronze, and other metals! - M. Demetrius - 05-30-2007
Quote:So, now I've got ot ask. What happens if you work the alloys when it is hot?I heated a brass buckle dull red hot, and smacked it with a hammer, to flatten the metal. It shattered, and sent several pieces of red hot brass into a pile of sawdust. Instant fire. You really don't want to do that.
Quote:I would go with working it hot myself, as that was what I had always understood, but why do people keeping giving the other answer?Blacksmiths always heat the metal, varying degrees of red to yellow hot, depending on what they're doing. Dull red won't help a lot, for working the metal, so you need hotter than a propane torch can generally provide. If you have a very hard, or hardened steel, such as a knife blade, heating to a medium red and letting the metal cool off slowly takes the "temper" out of the metal. In other words, it makes it softer. You can more easily shape, saw, file, etc., the metal, then if you know to what color-temperature to retemper it, that would follow.
Does that help?
Re: Working bronze, and other metals! - Gaius Julius Caesar - 05-30-2007
"Remember. To anneal the iron/steel, you have to let the metal to get cold very slowly. If you can put it into some carbon/ashes burning, and let the carbon with the iron inside get cold, iron will be soft as butter!
_________________
Cesar Pocinya
LEGIO PRIMA GERMANICA
www.primagermanica.com "
This is the reason I am a little confused. Not saying just you, Cesar, but several people have said the same thing........
Thanks Robert, that makes sense, and gels with what I remember from high school physics! :lol: