[Martin Wallgren]

I have a few questions about Pattern Welding! Hopefully They can be of interesst to others than me to...

1) why? as in why did this technic develope?

2) I´ve heard that it is done because the steel is not of a quallity enought to make weapons from it without this method. Is this true?

3) How late are there examples of swordblades in Europe made with Pattern Welding?

Hopefully our esteemed Swordssmiths frequenting this forum can answer this questions for me.

Have a nice one everybody. Thanks...

Martin

[Jason Elrod]

Actually I'd like to add one more question. . . How prevelant was pattern welding, really?

Petersen noted that Type H and Type M viking swords are the most common forms of the Viking Age. Of the 198 M type swords found in Norway, none had inscriptions and 2 were pattern welded. I couldn't find any info on the ratio of pattern welded swords to non-pattern welded swords on Type H specimans. However the info on M types got me thinking. Any one know the answer?

[Elling Polden]

As far as I gather, Pattern welding is a derivation of the lamination, or folding technique, used to increase the hardness of blades before high carbon steel was "invented."
Note that laminated and pattern welded blades are not the same; A Katana is laminated, but not pattern welded.
The lamination technique, as far as I've gathered, is indeed necesary to make a decent blade from iron or soft steel.
This tecnique produces a slight pattern, or grain, on the blade; The pattern welding takes this phenomenon, and cultivates it for decorative pruposes. The edges of the blade are still laminated, only the fuller is pattern welded(note the grain on the edges...):



So,
1) Because it's pretty.
2)Patern welding is not necesary, but lamination is, until high quality steel becomes available
3)In western europe, Patern Welding goes out of fashion in the 12th century.

Very nice illustration of the process:
http://www.templ.net/making_of_weapons/blades.php

[Jesse Frank]

Hi,

I should introduce myself. Well, my name is Jesse Frank, and I have been involved in bladesmithing for several years. I do mostly migration era/viking stuff, but I've recently been diving into the japanese nonferrous world of mokume gane. I like swords, long walks on the beach and quite moments with that special someone..... wait a minute, this isn't a dating service!

Anyway,
From the reading and experimentation I have done, twisted cores on pattern welded blades more than likely was initially done from a desire to produce more durable weapons. What originally was used was what is termed a "piled structure" where the whole thing is simply laminated together, or as straight laminated bars welded together to form the entirety of the blade. The problem with this, from an engineering standpoint, is that the things were likely to fall apart, as the only thing to hold everything together is the welds, which could be extremely inconsistant. When one twists a bar, several things happen. One, you create a mechanical lock with the layers of the iron, which will help stop crack propagation. Two, when twisting, the outer layer of scale and slag tend to break off of the bar, allowing for an easier, potentially more solid weld. You also have a visual representation of the quality of the construction.

Hope that helps,

Jesse

[Jesse Frank]

I should probably add that pattern welding isn't necessary with modern steels. Nowadays, when using modern alloys, it's purely for asthetics.

[Matthew Kelty]

Jesse has nailed the reasoning, benefits and results of the more fantastic patterns.

To address Question 2, and redirect a bit of what Elling had said, it's not that the laminating itself increases the hardness of the blades directly. The smelting of ore into Iron and Steel resulted in inconsistent results at best (Steel was actually a fluke there for a while). The Laminating process will integrate the various Materials, and their differing Carbon contents, and normalize the Steel content throughout the billet.

There's an excellent overview of the evolution of Swords and Steelworking at Anvilfire.com:

http://www.anvilfire.com/21centbs/armor/atli/index.htm

[Jesse Frank]

Matt brought up a good point. Good quality steel was a precious commodity. Many methods were used to stretch the supply. Most of the early viking/ migration era blades were extremely complex. Often, the edge would be a san mai style construction with low carbon or high/low carbon twisted cores sandwiched over another thin sheet of low carbon iron.

There are also examples where there are high carbon bands in the center of the blade, apparently to increase the performance. Tylecote has some really good books on the subject. I would recommend "metallography of early tools and edged weapons". I think that's the title, at least.

[Laurent Marshall]

First post for me too

A few questions to extend the discussion a bit:

- Why did pattern welding "go out of fashion" around the 12th century?
- When did new technologies or methods of manufacture make it obsolete from a practical standpoint?

[Patrick Kelly]

[Elling Polden]

The 13th century aestetic is also a lot more "sombre" than the 12th century; large embroderies on clothes become uncomon and so on. Likewise, the flashy patternwelded sword could have fallen out of favor in the same way.

it is also a question of price vs function. As monosteel swords gain acceptance, it is no longer profitable to spend several times as long making pattern welded swords, when you can earn more on making monosteel swords.

As a side note, as i understand it, the original Damascus blades where monosteel; beeing made from the relative high carbon Wootz steel they did not need to be laminated. (Correct me if Im wrong...)

[Matthew Kelty]

>As a side note, as i understand it, the original Damascus blades where monosteel; beeing made from the relative high carbon Wootz steel they did not

need to be laminated.

You are dead on, and this has only been really clarified recently. Damascus is one thing, and pattern welding is a completely different beast.

People have been using pattern welding for a few hundred years to imitate true Damascus, as the process for creating Wootz fell into disuse, and was

eventually "forgotten" in the 1700's. The truth of the matter is that the places where the Ore had all of the requisite characteristics was eventually

abandoned, and it was only a few communities that knew the truth to be a super-saturation of Carbon, a certain Alloy mix, and a sealed crucible

smelting process, combined with low-tempurare forging methods to retain the various zone boundaries.

At any rate, manipulating different materials through pattern welding could create the classic watered steel look of true Damascus, and for a the last

300 years or so, we've been calling the product "Damascus".

The lid was finally blown off by John D. Verhoeven in an article titled "The Key Role of Impurities in Ancient Damascus Steel Blades" from the

September 1998 "JOM" (A Publication of The Minerals, Metals & Materials Society):

http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html

and the January 2001 Scientific American:

http://www.mines.edu/Academic/met/pe/faculty/...mascus.pdf

Additionally, another gentleman found a similar production technique (in the Ukraine I beleive) called "Bulat" steel.
I don't read Cyrrilic, so i can't tell exactly what he's describing, but he basically does a photo-survey of him creating the Bulat/Wootz ingots in the

field:

http://www.geocities.com/qasruf7/bulat.html

So the last 5-8 years have seen bladesmiths fighting a battle to differentiate the two techniques in the eyes of the consumer.

Spread the word...

[Matthew Kelty]

Ouch! Sorry my formatting went wonky!

Anyone who'd like to edit that for readability may do so without hurting my feelings...