

Yes, the edge is different due to the forging process placing the harder steel on the edge and the asymmetry allows for less hardened steel. I've seen videos from the current Iwasaki razor shop where the blade length is between 3-3.5 inches, but they end up cutting off the tip to make it closer to 2.5 inches. Its kind of cool that they keep it within the traditional margins. I use mine with both my right and left hand regardless of the asymmetric grind.@Luecke3262 so it appears based on the photos that the common feature of a "kamisori" is the shorter blade lenght and the asymetric geometry. Clearly the overall shape and geometry result in a different edge as well
This is possible.@ShawnF I would like to see you make (me) a Kamisori. Make it demascus like the knife you made me for Christmas and you would be a razor making GOD!.
I've read the same about different hardness at the edge vs the rest of the razor. I have ZERO experience using any of the Japanese stones but I have to wonder if the composition of the steel and the geometry etc of traditional Japanese Kamisori blades were done with the Japanese stones in mind ...Because the Japanese are known to be very purposeful in their design.From the little info I was able to Garner outside of here , from what I read , the steel they are made out of is also a factor. You might find that a kamisori is made of two different steels. Hard high carbon for the cutting edge, and soft on the spine. It stated it was Something to be very aware of when honing. Also it said you might find that on some of the folding ones so I guess that is another thing about them to consider
Simple answer is the steel they had.I've read the same about different hardness at the edge vs the rest of the razor. I have ZERO experience using any of the Japanese stones but I have to wonder if the composition of the steel and the geometry etc of traditional Japanese Kamisori blades were done with the Japanese stones in mind ...Because the Japanese are known to be very purposeful in their design.
The forge welding process used in kamisori manufacturing is called Hagane-tsuke(attaching the steel). This is where the tamahagane(hard steel) is forged welded to the jigane(soft steel). You should check out some of the traditional kamisori making videos on YouTube, they are fascinating.Simple answer is the steel they had.
They were introduced to this type of razor by Chinese Buddhist around 550. Pretty much the only steel they had from that period all the way until after the edo period in the late 1800's was tamahagane.
Basic description, Tamahagane is iron sand smelted with large amounts of charcoal. The charcoal introduces carbon to the iron making steel. This is done in a very large open top clay furnace. The carbon migration is not consistent so the resulting steel is not consistent. Some is very high carbon making an excellent edged blade, some is medium carbon more suited for tools, and some is still basically iron.
Because it is so time consuming and not mass produced, the choice pieces go to sword makers making it somewhat rare.
To conserve the high carbon pieces (and provide strength) they were combined with low carbon steel or iron. This was also done with swords and knives.
I can't recall the term for 2 layers like the razors used, but san mai is 3 layers commonly used in knives. 2 outside layers of iron or low carbon steel with a high carbon core.
I believe that is just the process of forge welding mild and hard steel. I belive that is used across the board for forge welding dissimilar metals. I do not speak Japanese however, so I am not 100% sure, just the way I understand it when I'm reading things.The forge welding process used in kamisori manufacturing is called Hagane-tsuke(attaching the steel). This is where the tamahagane(hard steel) is forged welded to the jigane(soft steel). You should check out some of the traditional kamisori making videos on YouTube, they are fascinating.