[TheForge] Samurai program

[schade at acegroup.cc]

On Oct 6, 2007, at 11:36 AM, Bob Smolen wrote:

> I believe PBS is going to show a program on Samurai swords this coming 
> Tues. at 7:00. Check your listings if you are interested.
> Bob
> _______________________________________________
>

If you go to the Nova site there is an interactive slide show
showing some of the highlights of the show. In one segment they
say that the curve in the finished blade is made by quenching
(clipped/pasted below). I am not a knifemaker or student of
damascus/samurai swords/patternwelding/etc but I have never
heard this before.

Is it true?

Looks like a good show.

Bob

http://www.pbs.org/wgbh/nova/samurai/sword.html

launch interactive

"Curving the blade
Next, the smith pulls the katana from the fire and plunges it into a 
trough of water in a rapid cool-down process called "quenching." 
Because the sword's back edge and inner core contain very little 
carbon, they can contract more freely than the high-carbon steel at the 
front edge of the blade. The difference in both the degree and speed of 
contraction between the two forms of tamahagane causes the sword to 
bend, creating the distinctive curve. This is a tricky stage, in which 
as many as one in three swords is lost."