The welding Peter King refers to is not the welding of the present day.
It's the pressure welding of two very hot pieces of iron. I n the
present case, the blacksmith would have forged the axe blade somewhat
shallower from edge to back, and of a consistent taper (As well as
could be judged) from wrought iron. he would then have folded a strip
of steel plate, perhaps a quarter of an inch thick, to fit along the
edge of the blade. heating both in the forge, he would then have
hammered the sandwich down until the steel and the iron took the
required shape. At this stage the whole thing would be soft, and could
be filed and smoothed. Reheating the thing once again to a yellow red
heat , it would be quenched. probably in water. At this point the iron
would still be soft, but the steel would be glass hard, and brittle. A
good smith could do the next bit in the same process. The steel has to
be tempered, to prevent it shattering in use. Here's where the good
smith comes in. He would only quench the cutting edge and an inch or two
back. When black, he'd take it out of the water, scratch the edge with a
brick or some other abrasive and watch. The remaining heat in the back
of the blade would travel into the edge. The bright scratches would
first turn straw coloured, then deeper, eventually turning blue grey.
However, when the steel turned a mid straw colour, he'd quickly quench
the whole thing, until cold. The axe would the be tough all over, but
the cutting edge would be hard, but much less brittle. A few minutes
work on the grinding wheel and it's done. If polished, and I'm sure few
were, the steel and the iron would be subtlety of a different grey.
This is largely the effect that the Japanese swordsmiths are famed for,
and in a different place and time the smiths of Damascus.
Rod Goslin
On Thu, 26 Apr 2018 15:26:51 +0100
king peter <[log in to unmask]> wrote:
> Before the advent of mild steel (with the Bessemer process in 1860s)
> and Siemens-Martin Open-hearth process in 1870s, the body of edged
> tools was usually made of wrought iron. At the beginning of its
> fabrication, a strip of steel was welded where the cutting edge was
> going to be.
>
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