The Secret World of The Japanese Swordsmith

[@Th3Mavr1ck]

What a gem of a doc

[@NathanOkun]

Considering the high temperature of the quenching (hardening) heat treatment, the edge when cooled in pure water will very probably form the even higher hardness (and brittleness) crystal CEMENTITE along the extreme cutting edge of the blade with white (fresh, somewhat brittle) martensite forming the rest of the high-carbon tapered and outside flat blade portion and the less hard, but much tougher (ductile), center being crystals like pearlite or perhaps a form of bainite composition (bainite can be good or bad, depending on where it is and exactly what version of the crystals form -- there are knives that replace martensite with various bainite structures with good results). Fresh martensite has to be changed to yellow (aged) martensite, which has more "give" (internal toughness) on impact, to get a truly successful knife or sword. Tempering by reheating to a moderate temperature (well below the quenching temperature) after quenching is what is done now (even this has potential problems if not done properly!) but it can also happen at room temperature by simply leaving the sword on the wall untouched after quenching for a few years to very slowly on its own take the "kinks" out of the martensite crystal patterns. This video is amazingly informative!!!

[@evasanders7327]

Judging by the lack of sparkling that is some seriously high grade tamahagane

[@Deuceeg]

Remarkable craftsmanship.

[@Бислан-ж4ц]

Какой труд отлично 👍

[@RakkSoild]

ugg the secret of Japanese swordsmith is that they use 1000 year old technology rather then modern steel working. The only difference is that the old way is much slower. and that the only quality control is the smiths experience. Dont get me wrong it takes ALOT of skill to be able to use old school blacksmithing and make something this nice. but using modern blacksmith someone could have like 2 years experience and make a katana just as amazing in a 8th of the time for much much cheaper. Japanese swordsmiths choose to use the slow and hard way to make there swords art pieces that are expensive. Again its amazing to watch sand turn into a sword by hand. but because Japanese swordsmiths are so stuck in the old way of doing things less and less people are learning how to become blacksmiths. A katana that uses modern equipment like welding, powered forging hammers, modern steel, chemical bluing and etching can be way stronger, and much more beautiful. I can't stand when people think these swords are better just because they are hand forged.

[@ReiMonCoH]

It’s really not a mystery. Seriously, we know Every single detail.

[@atom8248]

Yeah lol, it's an unbroken tradition so obviously they know all of it. It's probably so it sounds really dramatic for tv to call it a mystery or secret though.

[@ReiMonCoH]

@@atom8248 no no… They know nothing. These people who pound steel like they still live in the dark ages haven’t got a clue. They know, do this or do that and it gets a particular result. I’m saying, at this point, we actually have an understanding of the combination of the actual chemistry involved in such detail that NONE OF THIS is any kind of “mystery” as our narrator seems to think. That’s all I’m saying.

[@atom8248]

@@ReiMonCoH What, have you ever talked to a swordsmith? I have and they know a lot more about metallurgy than the average person. Little of what modern science supposedly "reveals" about these swords wasn't already known.