Thread: Kamisorish project question

I keep eyeing up one of my swords to take a chunk out of and create a kamisori style razor. Its been bugging me for months. It is 1045 differentially hardened steel. From what I have gathered most razors are tempered carbon steel. I already understand how to NOT mess with an already tempered sword with power tool to not ruin the temper.

It should be around 40HRC for the body and 58-60HRC on the edge. Frankly after destroying one, I think their edge numbers may be a little high. In theory, will this take and hold a shaving edge? Any honemeisters willing to try it out after I wedge it out if I cant get it to shave my ever so forgiving face? Do wedges get a secondary bevel at the edge or do they get flat sharpened? Since there will be a consistent and slight smile to the edge and the spine, is it worth it to flat edge it or just leave it happy? Since the blade currently has a slight convex geometry to it, are there any tips to wedge it out faster since it will wind up so much shorter? Will the distal taper have an effect on the future honing of said razor? Are there any general standards on the attack angle of a wedge, should I work the spine thinner?

Back to the softer than advertised, the edge wont really chip like a hard edge, it rolls and bends. Distal taper is how the back of the sword gets thinner as you go towards the tip, just in case someone is not familiar with it. I am a bit too lazy and wont have access to a micrometer until at least the weekend for the edge angle, blade width and the spine thickness.

I hate it when I'm about to cut up a sword and I just can't get my hands on a micrometer until the weekend.

Michael

Moved to Workshop Forum.

Actually, you should be able to use a hacksaw to cut through the back of the blade without much effort.
For the 'skin' around the edge, you just use a dremel and take care not to let it linger in 1 place.
It takes quite a high termperature to mess up the temper. As long as you take care to watch the temperature, you'll be safe.

Originally Posted by Bruno

Actually, you should be able to use a hacksaw to cut through the back of the blade without much effort.
For the 'skin' around the edge, you just use a dremel and take care not to let it linger in 1 place.
It takes quite a high termperature to mess up the temper. As long as you take care to watch the temperature, you'll be safe.

Yea, I was planning on hacksawing it to length. then hacksawing to create the length of the shaving area up to about the shinogi-ji to create the shoulder. Then dremelling down below the shinogi-ji to create the handle, maybe leaving a bit of a nub at the far end of the handle for balance. I have about no concern for the temper on the handle area, but I did want to avoid destroying the hamon.

I am curious, what do you mean "skin" around the edge?

I was more wondering if it would, in theory, take and hold an edge good for shaving. Next up would be if anyone had any tips or tricks for turning it into a wedge from a convex shape (anti-hollow). I can take it to the stones with a steady hand and patience, thats how changes get made to the whole sword.

If you look at the cross cut of a Japanese sword, it is made up from different qualities of steel.
All are tamahagane, but not all parts are equal. The inner core is of a lower quality than the outer 'skin' that will be polished into a cutting edge. I've seen video footage of the process, and it is really remarkable how tight they can make the rough fit, before forgewelding and flattening / drawing out.

Anyway, the skin around the edge is of the highest quality. It is also the only part that is hardened, though admittedly, the skin often covers the entire sides of the blade. In this case I was referring to the ha. I didn't want to use Japanese terminology because most people don't know it, and it don't want to come across as a show-off.

Mind you, what I said only holds true for traditionally constructed swords. For monosteel blades, there is no difference between the various parts. of the blade.

Originally Posted by Bruno

If you look at the cross cut of a Japanese sword, it is made up from different qualities of steel.
All are tamahagane, but not all parts are equal. The inner core is of a lower quality than the outer 'skin' that will be polished into a cutting edge. I've seen video footage of the process, and it is really remarkable how tight they can make the rough fit, before forgewelding and flattening / drawing out.

Anyway, the skin around the edge is of the highest quality. It is also the only part that is hardened, though admittedly, the skin often covers the entire sides of the blade. In this case I was referring to the ha. I didn't want to use Japanese terminology because most people don't know it, and it don't want to come across as a show-off.

Mind you, what I said only holds true for traditionally constructed swords. For monosteel blades, there is no difference between the various parts. of the blade.

No way I would dice up nihonto. This is a chinese made monosteel sword, but it is differentially hardened. Actually the hamon, is not a skin, it exists completely though the sword. Its just the demarcation point between the tempered steel body and the hardened steel edge. I dont know an american word for it, so I will use hamon. Thats actually kind of a side project of this, to bring the hamon back. Its a cheap sword and the hamon is kinda weak, I also am not spending the big bucks on the traditional polishing supplies. So I will probably just base polish it good then do an acid wash. l am sure lots of people here have a clue how expensive japanese polishing stones are.

As a side note, there are a few other great forges and some good chines forges working with laminating different steel types in either traditional methods, or the more modern solid steel stock.

Nice picture of the internals of a hamon:



While on the subject, it is fighting me. I got a few hours on a DMT XC already and not too much of a dent. I threw on a quick n crappy 3 tape layer bevel, one side was awesome, 1/8th inch thick & straight. I got a forge wave on one side I need to work though. Its almost 1/4", and drops a hair by the other end, the other end did not actually work to the edge either. I also wished I would have picked up a DMT XXC. I have taken some pics of the endeavor. I am procrastinating on both finding the cable for my camera & putting it back on the stones. Are their any real preferences for the balance of the blade? I got this so it will balance on my finger right st the blade tang junction.

Well here we go

Rough template:



Rough cut (i left the knob on the end for balance, but it wasnt needed):



Main blank:



I have hours of rubbin on the DMT XC and slowly getting it into an actual wedge shape.

Sorry about the blurry pics, not used to this camera.

If you would have a way of getting a belt grinder to go slow (like a cheap dimmer switch) that would work too.
Dip in water, grind 10 seconds, repeat.

Originally Posted by Bruno

If you would have a way of getting a belt grinder to go slow (like a cheap dimmer switch) that would work too.
Dip in water, grind 10 seconds, repeat.

Yea, I dont have a belt grinder or sander. Its most of the way wedged though, I got a bit less than a quarter inch on both ends, its been expanding pretty even too. Slow and steady is the way to set it up right. Patience will pay for itself in the long run.