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efreysson
01-28-2010, 12:19 AM
I want to make a point of my characters protecting their swords against rust, and am currently writing a scene where one of them is rifling through various jars of blade coating before buying one.
Can someone tell me what kinds of oils/greases would be available for coating a sword in a low-tech society and European climate? And what kind of consistency/smell would they have?

Sarpedon
01-28-2010, 12:32 AM
naturally, there would be no petroleum derivatives. I recall reading that wax was sometimes used. Grease derived from animal fat is also a possibility. Swords in storage were not polished, and were allowed to form a protective patina. I recall reading that a huge portion of the armory of Saxony was preserved in that way.

waylander
01-28-2010, 01:01 AM
Lanolin from sheep's wool.

efreysson
01-28-2010, 01:17 AM
Lanolin from sheep's wool.

Hmm. Did they rub the wool itself up against blades, or was the lanolin extracted?

waylander
01-28-2010, 01:23 AM
Rubbed the blade with raw wool

justAnotherWriter
01-28-2010, 01:43 AM
There is some evidence that in some periods, scabbards were lined with wool, which would have contained lanolin.

Animal grease was definitely used, not only for swords, but for armor as well. Tallow, which was used to waterproof leather, could also be used to coat metal.

Much of this is speculative, but there are scattered accounts, such as mail being stored in buckets of animal fat until ready for use.

Sarpedon brought up another account about protective patinas. There are also accounts about rubbing the sword (I don't remember with what) to remove active rust but leaving the black stuff alone.

Just keep in mind that keeping the weapon pristine would not have been a concern of most people in the middle ages. Keeping it sharp and serviceable would have been the priority. On the other hand, we have perfectly preserved five hundred year old (or more) swords, such as the beautiful type XVIIIa in the Bayerisches Nationalmuseum in Munich, which would have been made for a wealthy patron who obviously took meticulous care of it, as did everyone it passed to after his death.

Canotila
01-28-2010, 01:54 AM
Also, if you don't wipe your fingerprints off before putting it away, it will rust pretty quickly. I remember being at a living history event near the coast and having my fingerprints rust onto my bayonet overnight. That was annoying. They buffed out, but still. It could have been prevented.

justAnotherWriter
01-28-2010, 02:07 AM
Also, if you don't wipe your fingerprints off before putting it away, it will rust pretty quickly. I remember being at a living history event near the coast and having my fingerprints rust onto my bayonet overnight. That was annoying. They buffed out, but still. It could have been prevented.

This actually depends on body chemistry. I know people who can cause rust in a few hours, and then there are people like me, whose fingerprints can be left on for days without harm.

Mike Martyn
01-28-2010, 02:42 AM
Smelll? Probably like rancid butter.

Canotila
01-28-2010, 02:57 AM
This actually depends on body chemistry. I know people who can cause rust in a few hours, and then there are people like me, whose fingerprints can be left on for days without harm.

I have the super secret power of corrosive fingerprints! Which, uh, makes it easier for forensic experts to identify me! Buahahahaha!

That's pretty cool though, I didn't know it varied for different people, but that makes sense.

justAnotherWriter
01-28-2010, 03:23 AM
Smelll? Probably like rancid butter.

I forgot about the question on consistency and smell.

I've personally used tallow, and it is like a block of brittle soap that melts at high temperatures. The way you would treat a sword is to break off a piece of it (it's a bit mushier than soap) and rub it into the steel, then maybe leave it in the sun (today we can use a hair drier) to get it to soften and spread into the pores of the metal.

The smell is not bad. Once it dries it has a bit of a beef broth smell to it, not terribly unpleasant. Eventually that smell fades.

BillPatt
01-28-2010, 07:20 AM
Modern firearms are 'blued', where black oxide, magnetite, is allowed to form on steel, instead of red oxide, or rust. From my favorite site, Wikipedia:



Bluing may be applied, for example, by immersing the steel parts of the gun to be blued in a solution of potassium nitrate, sodium hydroxide, and water heated to the boiling point.


It does not describe when this process was discovered or used.

Potassium nitrate is an essential element of gunpowder. Sodium hydroxide, or lye, was used in the production of soap. You got potassium nitrate from guano and lye from wood ashes. I see no reason why someone couldn't have discovered this process in a low-tech time.

Of course, you have to keep it oiled anyway. But it kept the evil corrosive fingerprints away.

justAnotherWriter
01-28-2010, 05:12 PM
Modern firearms are 'blued', where black oxide, magnetite, is allowed to form on steel, instead of red oxide, or rust. From my favorite site, Wikipedia:



It does not describe when this process was discovered or used.

Potassium nitrate is an essential element of gunpowder. Sodium hydroxide, or lye, was used in the production of soap. You got potassium nitrate from guano and lye from wood ashes. I see no reason why someone couldn't have discovered this process in a low-tech time.

Of course, you have to keep it oiled anyway. But it kept the evil corrosive fingerprints away.

Chemical blueing is a relatively modern process, but they did have blackening of steels in period. Heat bluing, oil blackening and painting were all used on armor (I'm not sure of the timeframes, particularly oil blackening, which may not have been used until much later). I don't recall any evidence that any of these techniques were used on swords, however.

hammerklavier
01-28-2010, 07:39 PM
Better yet, they should be parkerized! (I have a pocket knife that is parkerized, it's very cool).

Chrome plated would not be bad either.

Seriously, some blades were more resistant to rust than others depending on their composition... if they happened to have a certain amount of nickel then they would qualify as a rudimentary sort of stainless steel. But keeping the blade dry and highly polished was the main defense against rust.

BillPatt
01-28-2010, 07:41 PM
Chemical blueing is a relatively modern process, but they did have blackening of steels in period. Heat bluing, oil blackening and painting were all used on armor (I'm not sure of the timeframes, particularly oil blackening, which may not have been used until much later). I don't recall any evidence that any of these techniques were used on swords, however.

Agreed. The process, though, is very low-tech - stick the item in boiling chemicals. The chemicals themselves are not exotic. Depending on the setting, you could have someone 'accidentally' discover the process. But I agree - the process was not discovered until relatively late.