Working bronze, and other metals!

[Caius Fabius]

Back in the 1970's there was a newsletter for armorers (armourers) in the SCA. Many of the topics we discuss here are not new, and questions and answers were given in a quarterly magazine.

Luckily most of the interesting articles were preserved, and are available from http://quietpress.com

# Best of the Hammer Volume 1 - H1 - $14.95
# Best of the Hammer Volume 2 - H2 - $14.95
# Best of the Hammer Volume 3 - H3 - $14.95
# Best of the Hammer Volume 4 - H4 - $14.95

From quenching to annealing to making maille, to making swords, and armor,; working brass, bronze, iron, steel... if you plan on doing much work in metal these are excellent books, and cheaper than many of the blacksmithy tomes I have in my collection. I used these to make my university metalworking classes so much easier, (it's not cheating to have better sources than the teacher...)

[Caius Fabius]

I also just finished videoing a class on how to 'chase' brass, which included many helpful tips. Most important, ( for this thread) keep annealing the brass by heating it and quenching it, so it does not become brittle while you work it. You will feel it becoming harder, with a little practice, and know when to anneal it again. If I can get the teacher's permission, I may be able to make portions of the video available at a later date. It was a very good class for beginners and advanced beginners in 'fancy' but non-precious metalwork.

[Gaius Julius Caesar]

Thanks people, this is getting to the point where I am feeling confident enough to tackle something, soon!

[Marcus Julius]

I also just finished videoing a class on how to 'chase' brass, which included many helpful tips. Most important, ( for this thread) keep annealing the brass by heating it and quenching it, so it does not become brittle while you work it. You will feel it becoming harder, with a little practice, and know when to anneal it again. If I can get the teacher's permission, I may be able to make portions of the video available at a later date. It was a very good class for beginners and advanced beginners in 'fancy' but non-precious metalwork.

Caius, I would love to have that instruction if they'll let you make it available.

[Gaius Julius Caesar]

Ditto! Your up early Brian, up to do the chores?

[Marcus Julius]

No, bored at work on the graveyard shift.

I can tell you that without the internet, night watch on Hadrian's wall had to have been hell! :lol:

[Titus Publius Saturninus]

what about the use of mapp gas in place of the propane? It burns hotter

[Gaius Julius Caesar]

My torch burns a mixture of butane/propane! It's supposed to burn over 1000deg C. If I remember what the guy said! Can't find anything specific in the instructions!

Is that the same?

[Gaius Julius Caesar]

So... 2 questions!

1 - what thickness would be used for a pair of greaves?

2 - What thickness would be used for hammering a bowl out?(and I suppose the diameter would be dependant on the head size and helmet syle.....)?

Bronze and iron/steel!

[Titus Publius Saturninus]

Just a little info on Mapp gas

MAPP gas is a stable, high energy fuel offering excellent performance for heating, brazing, soldering, metallizing, flame cutting and flame-hardening.

MAPP gas is made by combining liquefied petroleum gas with Methylacetylene-Propadiene.

The neutral oxy-MAPP Gas flame produces 2405 BTUs/cf with a 5301° F (2927° C) flame temperature. MAPP-air flames also produce better results, much faster than air-propane

Cheers!

Titus

[AntonivsMarivsCongianocvs]

Salve,

The recreation greaves offered online range from 18 gauge (thinnest like most helmets sold) to 16 gauge (thickest); with the 16 gauge costing more… approximately $60 more per set…. Such as those at www.by-the-sword.com

I’ve had a difficult time locating any reference of the measurements of originals though.

I’m sure someone will post for you.

[Matthew Amt]

I don't think anyone has made it clear that steel (and I believe wrought iron to at least some degree) CAN be worked either hot or cold. As it gets cold it work-hardens, and you have to reheat it. You can either heat it up red-hot and start pounding on it right away, in which state you can do pretty much whatever you want without stressing the metal. Or you can anneal it by heating it red-hot and then cooling it off as slowly as possible. And THEN work until it's work-hardened again. Either way, go too far with the cold working and it will crack, though you may be able to forge-weld it back together (easier with wrought iron than modern mild steel).

Remember, both ferrous and copper alloys will vary dramatically in hardness and workability depending on the content of carbon or tin (or zinc). A high-tin bronze is actually harder than wrought iron or low-grade steel, but it's not as malleable and workable. Brass isn't as hard as bronze, but I don't know exactly where it falls by comparison.

18-gauge (c. 1mm) seems to be a very typical thickness for ancient armor and helmets. Some were a little thicker, many were thinner. The weights I've seen for helmets tend to be less than for most 18-gauge repros. But the information is very scarce and hard to find!

Valete,

Matthew

[Gaius Julius Caesar]

So perhaps for an amature, a thicker guage would be more forgiving?

The supplier who sent me info lists a couple of different percentage phosphor bronzes, as well as aluminium bronze, and another!

I tried to post the info, but RAT rejected the file type. Pity, as it sems interesting, and mentions which properties each type has.....

Thanks for the info guys, it is all helping!

[Matt Lukes]

For annealing special fuels aren't really cost-effective I've found, however it's very useful to have a multiple-flame torch head like this one:
[url:3k87262l]http://www.bernzomatic.com/bernzomatic/consumer/jhtml/detail.jhtml;jsessionid=UV3ANUX235CB2CQHUB2CGWQKA4QGIJCK?prodId=BernzoProd100073[/url] it comes with a bottle of MAPP gas, but the torch tip works just fine with propane too.

Or this one: [url:3k87262l]http://www.bernzomatic.com/bernzomatic/consumer/jhtml/detail.jhtml?prodId=BernzoProd100019[/url]

The usual pencil-flame tip is a lot slower because it heats a rather smaller area.

[Northman]

The key points to remember about heat-treating and annealing metals.

Copper, and it's alloys Bronze and Brass, anneal by heating them up to a dull red color and then quenching/cooling quickly in water. If you let them cool slowly, that will harden it.

Iron, and steel (iron with carbon mixed in), anneal by heating them up to a dull red and then letting them cool slowly. You harden them by quenching/cooling quickly in water or oil. How hard you can get them depends upon how much carbon is mixed into the iron.

You can work both types of metal cold, but both will work-harden - and crack/split if you work them too far. With a little practice, you can learn to feel the way the metal is reacting to your hammering, and know when it needs to be annealed (made softer) again.

Iron and steel can be worked either cold or hot. The metal moves and shapes easier when it is hot, and you can shape it into much thinner and more complex shapes when it is hot. But you can also do simpler shapes by hammering the cold iron/steel. I have made a number of Riveted Sheet Iron Kettles by cold hammering the iron pieces to shape. A lot of armor pieces could be formed the same way.

How much can you work iron/steel cold? Well, I have formed up several dozen 1700's era sheet iron trade pipes out of 18 guage - all hammerred/worked cold without annealing the iron - either before or during the forming. I worked it slowly, but never repeatedly bent/straightened any parts. None of the ones I made split or developed cracks.

Copper and its alloys should be worked cold - and annealed often. But a small amount of work can be done hot. You do have to be very carefull not to over-heat the copper, though. There is a fine line between getting it hot enough to forge, and having it all suddenly melt into a puddle! I have forged up replicas of Copper Culture knives, spears, arrowheads, awls, and fish hooks by forging them hot. I heat the copper up to where it just starts to glow red, and the start forging. You loose that red color quickly, but you can continue hammering a long time. But you will soon "feel" the copper hardening up as you work. I then heat it back up and continue working. When I had the pieces forged to shape, I then continued to lightly hammer them as they cooled completely - to work-harden them. But forging copper will tire you out fast! With iron/steel, you get some "rebound" when hammering it. With copper you don't get any rebound. It is a dull hit. So your arm has to work harder each time. An hour of forging copper is like 2 to 3 hours of forging iron/steel.

So go ahead and hammer form your sheet iron/steel and copper/brass/bronze cold. Just anneal them as needed.

And then there is a Silica-Bronze alloy. It is specifically formulated to work and forge HOT - just like iron/steel. Great stuff! A friend forged up 35 feet of railing using it - with lots of flowers/vines/branches/scrolls in it. She then had it sand-blasted down to clean/bare metal, and then she applied several acids/chemicals to bring out the right Patina. A final clear-coat of epoxy sealed it all in. Great looking project!

Just my humble thoughts to share on this. Take them as such.

Mike Ameling - out in the Hinterlands