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MAKING DAMASCUS
Why Damascus? It is beautiful, has
integrity, ultimate cutting edge, no two the same, tough, unique, hard to
make right, indestructible, and a joy to own.
The
blade steel is 224 layers of 0-1 tool steel, S-2 shock steel (jackhammer
bit steel) and mild steel. The
blade is made by starting with two 3/8” layers of S-2 steel, one
3/8”layer of O-1 steel and 4 layers of 1/8” mild steel. They are stacked with the mild steel on
the outsides and between the layers of O-1 and S-2. The width is an inch
and is about 3 inches long.
A
handle is arc welded on one end to hold the piece when hammering. The whole thing is brought to a forge welding
heat in the forge and fused together under the hammer. It is then drawn out to about twice the
original length, cut almost in half, brushed and folded over with the
addition of welding flux (anhydrous borax) and fused again. This process
is continued until 224 layers are formed.
CHISEL CUT
1. 2.
3.
4.
The
finished blank is drawn out to a tapered shape about 1/2” thick. The
surface is textured by grinding grooves and possibly drilling shallow
holes on the flat surfaces. During
the high heat required for forge welding, carbon migration between the
different steels is stopped by the high silicon content in the S-2
steel. In this way the
individuality of each steel is maintained.
SHALLOW HOLES
MAKE BULLSEYES
GROOVES
ON BOTH SIDES CREATE A LADDER PATTERN
THE
GROOVES CAUSE THE STEEL TO BE SHIFTED SIDE TO SIDE SO MORE LAYERS
CROSS THE CUTTING EDGE.
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When
the bar is hammered to almost finished blade thickness, the grooves and
shallow holes are lifted to the surface.
After grinding to outline shape and final finishing, the tapered
edge of the blade is hammer packed along the cutting edge to reduce the
grain size of the different steels.
A
good blade can also be made by twisting the finished billet after it is
forged round. When this is hammered out flat the twist pattern, known as
Maiden Hair, is evident. It is next to the ladder pattern for increasing
the number of layers crossing the cutting edge.
LADDER PATTERN TWISTED PATTERN
WHITE AREAS PATTERNED WITH
RANDOM PATTERN
Another
beautiful pattern is what I call “Eagle Wing Damascus”. Here I try to force the
pattern to look like wing feathers. This is accomplished by grinding
diagonal lines and inputting several bullseyes.
After
grinding the sides and handle section, it is polished. After the initial polishing it is
hardened at the forge, repolished, tempered and polished again. Next it is acid etched in hydrochloric
acid. The acid eats away at the
different steels at a different rate so that a one of a kind pattern is
visible on the blade. After rinsing, the blade is coated with a brass
black solution (like gun bluing) then polished with a worn 600 grit
sandpaper. This highlights the
raised portions of the steel pattern and leaves the recessed layers dark
so that a beautiful contrast is achieved.
The
mild steel tests out at a Rockwell hardness on the C scale of 45. The S-2 tests at 59 and the O-1 between
62 and 64. The result is three
steels with different hardness crossing the cutting edge many times. The
grooving of the steel maximizes the number of times the layers cross the
cutting edge. The result is a
miniature saw edge with different steels of different hardness that wear
away at different rates and in effect self-sharpens for a period of
time. As the mild steel wears away
first the O-1 and S-2 steel is left behind for maximum cutting. It stays
sharp and also sharpens easily with a very light pressure on a ceramic
sharpening rod. Use a quality
ceramic such as Coors ceramic distributed by Spyderco knives.
This
type of laminated blade cannot break easily. The many layers do not allow a crack to
propagate through the blade. Testing has shown on one my blades bent to
90 degrees and hammered flat on an anvil, cold,
did not show any sign of stress or breakage. This was a combination of
O-1 tool steel and mild steel The blade had to be bent to almost 180
degrees before the outer layers crack. Even then the blade did not break.
Because of this a Damascus blade is a real survival
knife and will out perform any single steel knife. My newer blades may be
more less tolerant since I have incorporated lots
of S-2 jack hammer bit steel in the layers.
Damascus
steel is beautiful and has a superior cutting blade if forged properly
from the right combination of steels. Since 1977 I have been
experimenting with different steel combinations and have chosen the
steels I use because the blade is tough, pretty and durable. The S-2 is
used because it stops carbon migration and by itself as a blade can cut
any other blade ( i.e. buck) in half without any sign of chips or edge
loss. This was demonstrated at a
workshop with 45 smiths in attendance wher | 