Thursday, September 25, 2014

a Pattern Welded Sword...

Since my return to Wareham, I have been working seriously on a (slightly) postponed commission : A Norse type pattern welded sword *

The two starting blocks were composed of a total of 13 individual plates :

M-I-M-L-H-L-M-L-H-L-M-I-M

M = MILD STEEL, inner at 1/8", outer at 3/16"
I = WROUGHT IRON, 1/4"
L = L-6 (nickel mid carbon alloy), 1/16"
H = 1095, 1/8"
All pieces at 1" wide x 6" long

After welding to blocks, each was drawn to a rod roughly 70 cm long x 12 cm.
Next each was facetted to octagon, then given three sets of twists (alternating with straight sections).
The two  cores were forged square, and fitted to two pieces of 1045 (coil spring) and prepared for the next stage.

Rods wired, prepared for welding
Showing starting length
Detail of tip construction


At start of welding, the bundled rods were roughly 80 cm long X 5 cm wide X 12 cm thick.
There are two possible ways to fit the mid carbon steel cutting edges, a one piece wrap or two separate pieces. Both present their own forging problems, in the past I have chosen the two piece method. (The challenge here is welding tight the small triangle where the four pieces interlock.)

The welding process took me 3 1/2 hours, something like 16 (or more?) individual welding heats. The first cycle over overlapping 'travelling welds' were all done by hand. This was followed by a second series of heavy compaction welds using the air hammer.

After welding, note length and width change
Detail - The tip after welding
The finished billet produces roughly 95 cm of solid material (it is expected to cut at least 5 cm from the tip end).  At this point the billet is roughly 4 cm wide and 12 cm thick. It currently has a weight of 3.2 kg.

The next step will be to grind the surface down, removing surface flaws in the welds. These are primarily caused by the slightly rounded edges of the individual cores and edges. Some of the excess weight will be lost at this step.

In the creation of the final sword, this represents close to 2/3 of the actual work - and most certainly the majority of the difficulty.


* There is a lot of confusion on language here.
I use 'pattern weld' the way I first learned the term - as the archaeological definition :
Two or more layered rods, twisted, which form the core of the blade.
The starting stacks combine separate low and higher carbon plates, usually as low layer count.
The twists will alternate and match with clockwise and counter-clockwise direction, often including straight sections.
Most commonly a separate mid to high carbon rod is welded to each side of the cores to form the actual cutting edge.
The method was used primarily in Saxon and Norse blades, known samples ranging roughly from about 400 - 1000 AD. The ultimate example is the complex blade from the Sutton Hoo burial (a royal status object, consisting of eight individual cores, mirrored in pairs side to side and top to bottom. It was most likely created in modern day north Germany or south Denmark, about 600 - 625 AD.)

The Sutton Hoo Sword (in the British Museum)
 from : http://dailymythogies.files.wordpress.com/2011/03/p10102341.jpg

Replica created by Scott Langton
from : http://i292.photobucket.com/albums/mm36/cerishields/SuttonHoosword-resized4.jpg

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February 15 - May 15, 2012 : Supported by a Crafts Projects - Creation and Development Grant

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