hamon

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The Tori Tanto is a Chinese made replica of a Japanese tanto knife. Mine arrived today, and I have to say, I am impressed. It is one of the first 50 that were made with T10 steel instead of the Swedish powdered steel Hanwei uses. They were recalled, but this one got away.

My first impression was “this is a big knife!” The blade is 11”1/4. Overall length is almost 17”. I had to grab some junk mail on the kitchen counter and cut it.. Wickedly sharp is an understatement. The blade goes through paper almost like it wasn’t there. The mount is solid, with a very nice ray skin tsuka. That grip won’t slip, that’s for sure. My blade is not folded, like the new ones. The hamon is very prominent and looks artificially enhanced, something I wish Hanwei would stop doing.

Cutting palm fronds was very easy, as you’ll see in the video. The Tori Tanto cuts even better than my Cheness Kaze Ko Katana. I did not want to try it on bamboo. It would be a shame to scratch that blade. I know what the result would be anyway, given how sharp it is.

The tanto must have been a formidable weapon in it’s time. They were worn by Samurai inside as a backup, when wearing a sword was impractical. A skilled swordsman could probably chop a wrist clean off with one of those. It is still as formidable today as it was then, as far as self-defense goes. My interest in knives has always been about how such a simple tool can take so many forms, as well as metallurgical and historical factors. The Tori is a lot of knife for the money. Priced at around $300 new, I believe it would still sell at twice that amount. So, when I found mine at $230, I couldn’t let it go.

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[warning]A carbon steel blade such as the Tori Tanto must be cleaned and oiled after each use and you should never touch the blade with your fingers after that operation, otherwise, it will rust.[/warning]

Like I say in the video, if you are hesitating about buying one, don’t. I have no affiliation with Hanwei, but I recognize quality when I see it. Other than the enhanced hamon (hardness line), the Tori Tanto is close to perfection.

I have been pretty busy forging, with the completion of a scimitar inspired knife out of a railroad spike, hardened in water, and a sort of tanto for my friend Phil who provided me with steel for a new anvil and helped me build it. The tanto was differentially hardened using the clay method with Satanite refractory cement and transmission fluid for the quench. But first, here is a photo of the scimitar (the handle is parkerized), sheath by Robert Jones:

Railroad Spike Scimitar

Railroad Spike Scimitar

Below is a photo of the parkerizing process for the handle, about ten minutes at 190F in the manganese bath:
Parkerizing

Parkerizing

The tanto was forged from a 1075 steel flat stock. I made one mistake in the claying process, and that was to heat-up the blade for quenching without letting the Satanite dry properly. this caused cracks in the covering, and uneven areas of hardness.
Tanto Steps

Tanto Steps

The objective of this operation is of course to obtain a very hard edge combined with a soft back. The result is a sharp blade that holds an edge but does not break easily. The quenching process was quite entertaining.
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The knife was tempered in the kitchen oven twice 1h30 at 450F to soften the metal a bit. 1075 quenched is too hard for a knife, the blade would chip too easily. The hardening succeeded, because the file I used to clean-up the blade would bite on the back of the blade, but skid right over the edge.

Next was polishing with sand-paper in the following grits: 100, 220, 400, 800, 1000. I could not remove all the file marks and some imperfections due to poor hammer technique (this being really my second completed knife), but the result is still pleasant. I did sharpen the edge, and it shaves nicely. For the handle, I used a piece of wood I had laying around, traced the contour of the blade on it and carved the inside with a narrow wood chisel.[warning]As much as the forge environment is dangerous, working with a wood chisel scared me quite a bit. I came close to gash my hand open with this tool, and I now have a lot of respect for it. Be VERY CAREFUL working with a chisel, trust me on that one…[/warning]

Carving handle

Carving handle

I had some PC-7 epoxy and decided to use it to glue the two sides together and fill any small void. The photo below was taken before I wiped the excess off. I will let it dry for 48Hrs before sanding down the handle to size.
Gluing the handle with epoxy

Gluing the handle with epoxy


I was going to wait before posting this last part of the series that I finished the handle, but I don’t seem to be able to find the time to sand it down to size. You’ll have to use your imagination. I am about to get a new propane tank and start on a new tanto, this one with proper tapering and better claying. I will post it when finished in a new post.

So, you want to forge knives… Well, I just started myself, only made a few blades so far. I have learned some information useful to beginners that might not be readily available online, or scattered all over the place. These lessons learned might save you some time, aggravation, even a few dollars.. Follow any advise here at your own risk, I am no expert and forging is inherently dangerous.

About forging: Forging is not just that, hammering a red-hot piece of steel into a blade. You need to consider what else comes into building a knife. A lot of time will be spent grinding, sharpening, and polishing. If using sand paper gives you unpleasant goosebumps, or you cringe at the thought of getting burned or cut, you might want to look into knitting. Heat treating is not as simple as plunging your steel in water. Some knowledge of metallurgy about different steels and what happens to them at different temperatures is a must. Annealing, normalizing, hardening and tempering are important phases in creating a blade. Then you need to make a handle, sheath, and sometimes apply different finishes. Building a knife is a whole process, forging is only part of it.

Forge: I started by building a charcoal forge. It worked, but it is slow and dirty, a pain in the ass, really. Sure, It only cost me $60, and I could have built a better one. Gas however is fast and clean. I bought a $200 forge on Ebay and never looked back. The next one will have a round shape though, and be covered with refractory cement instead of KAOWool. A round forge body creates vortexes resulting in a more even temperature and probably gas saving. With a hard refractory coating, you will never breathe dangerous ceramic fibers.. Coal is another good option, also dirty, but better in my opinion than charcoal. See my gas forge here.

Steels: Many beginners will try to find some scrap steel at the junkyard. You might get lucky finding what you want, but you might not. Spending hours hammering steel to find out that it won’t harden is no fun. I just ordered six 3/16 x 1” x 60” bars of 1080 from Admiral Steel for about $90 (with shipping)! That is enough to make from 30 to 40 large knives. Less than $3 per knife. Mystery steel is like mystery meat, you really don’t know what’s in it and most of the time, it doesn’t turn out to be that good. 1075-1080 is probably the best steel to start with. It is a simple steel, easy to heat treat and forge. You can temper it in a kitchen oven at 450F. Tool steels and other higher carbon steels require better temperature control and higher tempering temperatures, around 550-600F. It isn’t worth my time fishing for scrap in a junkyard. I would probably often have to discard half-finished blades, so the savings are really not significant enough. Buy good steel, pick one kind, learn it well, you’ll get consistent results allowing you to refine your process. More on steel selection.

Heat Treatment Anneal every time you stop working for the day. Normalize three times before hardening. Use a magnet to determine when the steel has turned to austenite and is non-magnetic. Go slightly higher, and let the blade soak for ten minutes at that temperature. If you forge or heat-treat too hot, your steel will decarbonize. Quench in warm oil (140 to 160F). Cold oil will actually not cool your blade as fast. Avoid motor oil, it’s too thick. Thin oil, such as ATF or thin mineral oil is better. Don’t move the blade sideways while it cools, but front and back. If you want to create a hamon by differential clay hardening, cover the back of the blade with a refractory like Satanite (1/8” thick layer). Temper immediately after hardening, three times one hour at 450F. If you use a different steel than 1060-1075-1080, find out what the numbers are, don’t just guess..

Anvil: I bought a cast iron anvil at Harbor Freight. It is way too soft! Here is when a trip to the junkyard might save you money. A 100Lbs hardened steel anvil will cost you $400 to $600. Find any piece of steel with a flat surface, as heavy as you can carry. Secure it to a solid base, so that you can forge standing up. Thanks to my friend Phil and his father at Seaboard Steel, I was able get a heavy piece of steel which originally was a jaw that grabs giant steel plates. It must be heat-treated because it is very hard. We welded it to an I-beam and a half-inch steel base.

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Hammer and tongs: Almost any hammer will do (you might want to put a nice smooth finish on it’s face), but you need tongs to grab your blades. I started with a pair of wise-grips, but they are too short and awkward to use. Having a piece of red-hot steel fly out when you hit it is pretty scary. Don’t ask me how I know.. (well, I still have one scar on my ankle..) Start by forging tongues. It is easier than forging a blade, and you will need them anyway.

Click on the image to enlarge..

Not the best looking ones, but they work just fine..

Safety: Wear heavy leather gloves and clear eye protection (clear to see steel color). I have a welding jacket with leather sleeves that’s perfect for forging. Make sure nothing close to the forge can catch on fire. That includes your propane hose in particular! Wear a respirator when grinding or changing your ceramic fiber forge insulation. Don’t forget, you’re building knives, they can get really sharp! Blades can fly off your hands while grinding, specially when using buffing wheels. You must be conscious of safety all the time. You don’t want to end-up in the hospital or dead because of a hobby!

Information: It is easier to start with some help. Browse the following forums online:

Document you progress. You might discover that a blade you forged displays great characteristics after some use, and not remember how you made it..

I highly recommend Wayne Godard’s $50 Knife Shop book:


Wayne Goddard’s $50 Knife Shop, Revised
And Tim Lively’s DVD:


Knifemaking Unplugged

I will add to this article once in a while as I discover new tips or pitfalls to avoid. Anyone with more experience than myself, that’s almost anybody able to forge a decent knife at this time, please add any advise for beginners you may have in the comments section below. Many thanks to the members of bladeforums.com for their feedback on this article!

UPS finally dropped my much anticipated Kaze Ko-Katana outside of my house last night (they didn’t bother to knock on the door, as usual). You might want to read the introduction to this full review here.. I am not a sword afficcionado, but I do know quite a bit about knives. This is my first katana, and I will try to provide an objective and complete review, though I have no other sword to compare it to. The closest would be my Cold Steel Master Tanto; apples and oranges..

Initial Impressions:

The sword came in a nice wooden box, cheaply made, but nevertheless attractive and practical. A lined sword bag is included, also much appreciated for the price.

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My first impression upon picking up the Kaze was that of a solid chunk of steel, well built and fitted. There is no “rattling” of any kind, nothing moves. The blade feels heavy, though I am sure not as much as a full size katana, which I have never handled. The short blade makes it comfortable to hold. For a beginner like me, it is important to track your blade in space as you move it around. Friends, pets and significant others will appreciate that.. Better have nobody around actually, that is much safer. Two things jump at you while looking at the blade: The natural hamon looks great. It is subtle, but obviously authentic in it’s beauty. The kissaki (tip) however is awful. More on that later. The sword feels very agile.

Specifications:

The blade is short, 20.5 inches. Mine has a brown cotton ito wrap, which is very tight. As I understand, it is also available in black. One menuki (handle ornament) is located on the left near the tsuba (guard), the other one on the right near the kashira (pommel). They feel good under your fingertips and improve your grip. The mekugi (pins) are set at an angle, which I guess is to clear the ito wrap so that the tsuka can be removed without unwrapping the handle. One is bamboo, the other one appears to be brass. I don’t see how the blade could possibly come loose with this setup. The saya (scabbard) is lacquered glossy black, and attractive from the outside. There is no reinforcement at the mouth, so I expect it to crack soon or later. Except for a slight difference in blade length, the specifications are pretty much what Mark Mowrey has in his excellent review.

The Blade:

The blade is made of 9260 spring steel with a differentially hardened edge by the traditional clay method. As mentioned before, the hamon looks great. I would not want a fake hamon except for a back-yard beater, and even then.. Fake is just that, fake. One might argue that a blade forged in China is fake, but I disagree. Chop your finger off, and see if fake blood comes out.. The polish is decent, certainly sufficient for a $200 sword. The kissaki however is the hair in an otherwise delicious soup.. I can see file scratches on the tip, as clear as day. It looks like someone was doing a great job on the blade, then ran out of time and thought “the hell with it, it’s done.” I would have been glad to pay $40 more for a decent job. Lucky me, I own a Dremel! I can imagine people raising their eyebrows there, but remember, this is a cheap sword. I couldn’t get it any worst than it already was anyway. I went to work with a buffing wheel and polishing paste. The look improved slightly, but not as much as I hoped. I just didn’t want to waste any time on it, as I was eager to fill some plastic bottles.. Sharpness at first was disappointing. The edge was sharp mind you, but did not shave hair like my Master Tanto. It did cut paper well, but not every time. I worked on it for a few minutes with a fine stone, then took it to my leather belt. Finally, I managed to clear-up a bold patch on my arm. With the proper tools and a little time, this blade could be frighteningly sharp. Time to head for the backyard!

Though I tagged the following video as a “cutting test,” it was my first ever cutting session. My lack of technique is obvious, but I managed a couple decent cuts. 2” palm frowns offered no resistance at all. My friend Erin brought his stainless steel wall-hanger fantasy sword for a try. We made sure the area was clear in case it came apart. No such concern with the Kaze.

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Oh, and by the way, the dog is fine!
[warning]This 15 minutes impromptu cutting session was long enough to allow tiny rust spots to appear. Wipe your blade regularly while practicing, and oil it when you are finished.[/warning]
Click on the image to enlarge..

My second cutting session was very educational. I went to cut palm frowns in the backyard. Sometimes the blade would go right through with no resistance at all, and sometimes I would feel a vibration through the tsuka. Re-enacting my movements slowly showed me that I was rotating my wrist, getting the wrong angle at the time of contact. As much as 15 to 20 degrees off! No wonder the frowns would just break sometimes. After correcting my grip, I could barely feel the cuts. This tameshigiri business isn’t easy. With my new confidence, I moved the the bamboo we have in the back.. It proved harder to cut, but with the right angle and swing, chop! 3/4” (nothing thicker in the yard), that’s enough for me, I’ll need much more practice before trying anything harder.

Verdict:

Historical accuracy: 3/5 – I don’t know! I am sure it detracts quite a bit from an original though.
Fit and Finish: 3/5 – If it wasn’t for the kissaki, I would have given it a 4.
Handling: 4/5 – It feels great in my hands. The short blade is quite fast.
Structural Integrity: 5/5 – I don’t see how I could possibly break it in normal use.
Value: 5/5 – Unbeatable price for a hand-forged sword with a real hamon.
Overall: 4/5

Pros: Cheap. Very strong. Beautiful hamon. Tight fittings.
Cons: Rough kissaki. Not as sharp as I thought (easy to fix).

Conclusion: A very good sword for the price. I tend to look at safety first when buying a practical weapon. The Kaze Ko-Katana does not worry me a tiny bit in that department. I do not think you can find a better deal for a hand-forged, differentially hardened blade. If Cheness spent a little bit more time on the tip, they could sell this sword for at least $50 more, if not $100. I am not worried about bending it on a bad cut either. It would take quite a mistake to bend it permanently. If the kissaki had been as well polished as the blade, I would have bought a Tenchi for cutting. As it is, the Kaze will be my backyard cutter. If I damage it, I can always buy another! I would recommend it to anyone, especially as a first time sword purchase. Even if you are not into cutting, it can make a nice display piece (polish the tip!) or an excellent home self-defense weapon.

After weeks of consideration and research on the web, I finally decided to buy a katana. Not a cheap wall-hanger, but a practical sword, forged by hand and differentially hardened. I am very familiar with knives, even started to forge my own. Swords however are mostly unknown to me. Why would a grown man buy a sword you may ask, well, I have a few reasons, and they have nothing to do with the “cool” factor. Swords are not toys, but deadly weapons. I place them in the same category as handguns and rifles. I came to believe that they are one of the best home defense weapons available. My interest in knives came from the staggering number of designs found for such a simple, primary tool. Metallurgy, the forging and hardening processes have always fascinated me. I have barely scratched the surface of that art, but I can certainly appreciate the skills it takes to forge a blade longer than a few inches, then harden and temper it properly. My life-long interest and practice of the martial arts also influenced my decision. I have long ago found out that most Asian disciplines only work in their context. Russian Systema however works in any circumstances and can make use of any weapon. Give me a frying pan and I’ll be immediately efficient with it using Systema principles. A sword, though presenting some challenges, shouldn’t be too much trouble. Of course, I will use a dull one or bokken for practice. Other sword designs were interesting, but the Japanese katana in my opinion is the best sword. It is light, razor sharp, and simple in design. Nobody wears armor these days, so a heavier sword would make little sense. The way these swords are made is also fascinating. Even if you have no interest in swords, you can’t but admire the dedication and skills of Japanese sword-smiths in their pursuit of perfection. I never get tired of watching the following documentary from National Geographic:

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I can’t pay three highly skilled artisans for three months to forge me a blade, so I have to accept some technological shortcuts. Modern steels like 9260 Silicon Alloy Carbon Spring Steel are even better than traditional tamahagane. It’s not traditional of course, but much cheaper. The folding process becomes superfluous, since the carbon content of modern steel is constant throughout the material. I would love a folded blade, but the cheapest ones, forged in China, start at around $1000. More than I am willing to spend for a first purchase. A San-Mai construction like my Cold Steel Master Tanto would be desirable too, but simply too expensive. There is one feature I really want however, and that is a differentially, clay-hardened blade. This process of covering the back of the blade with thick clay before quenching in water produces a very hard edge and a soft back (watch video above). This way, a sword will bend but not break, while still holding a razor-sharp edge. It also produces a visible line of hardness called the hamon. Most replicas have a fake one, acid-etched on the blade. I can’t accept “fake” anything, so my choice becomes fairly limited for an affordable real sword. Thanks to companies like CAS Hanwei and Cheness Inc., real forged blades from China are available, starting at around $160 for something that won’t come apart in your hands and take a lot of abuse before breaking. Shell-out $200 to $300 and you get a serious tool. My choice is the Kaze Ko-Katana. With a 21-inch blade, this katana is about seven inches shorter than a regular sword. These swords are also called chisa katanas, and are easier to use in tight places. Here is another review of the Kaze (watch the cutting test video). I got a 10% discount and ordered mine for less than $200, with free shipping.

Proceed to the full review