Hand-forged katana: Step 6, quenching and tempering
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- เผยแพร่เมื่อ 6 ก.ย. 2024
- This is the sixth video in a series. I'll be uploading a new video approximately every week as the project progresses. Each video will cover one step of the process.
In these videos I forge Japanese blades by hand. I heat treat them, polish them, and make all the parts necessary for mounting them. These videos are targeted to people who are interested in metal art, blacksmithing, forging, knife-making, and sword-making or are simply interested in maker videos. I try to present content in a calm, relaxing fashion that anyone can enjoy watching, whether you participate in this hobby or not.
My most recent blades are made from modern high carbon steel, such as W1 drill rod and custom W2 steel bars. In the future I plan on smelting my own tamahagane and making swords and daggers from that ancient steel.
katana, wakizashi, tanto, habaki, fuchi, kashira, menuki, tsuba, tsuka, quench, temper, hamon, asmr, tamahagane, W2 steel
Idc what anyone says about swords, I consider sword making an incredible form of art and not a waste of time its kind of like making a deadly clay sculpture you can make anything you want
Agreed. 99.9% of swords crafted today are for display purposes, but its the fact that this art is technically still a functional tool of lethal combat that gives it such mystique. It will always be beautiful to behold hanging on a wall or sitting on a mantle....but should the world come crumbling down it will still be capable of defending your life
Thanks for posting this and addressing the water temperature. I have a wakazashi-ish piece that I will be quenching in a couple weeks and am a bit on edge about the risk of cracking.
Good luck!
Keep growing love from India 🇮🇳👳 I'm mechanic, kalaripayatt practitioner and ayurved knowlege seeker
I love shinshinto katana and all blades 😁👍
Thank you, friend.
Brilliant way of tempering the sword. I've never done a water quench. That has to be nerve wracking. Outstanding job!
Thank you! I can't take credit for the oil tempering idea. I stole it from Walter Sorrells.
I'm Brazilian and your video was exactly what I was looking for, thank you very much.
I'm so happy you like the videos. There are more coming!
118 is ideal, but difficult to precisely control.
Interrupted quenching isn't as bad as a non-interrupted quench. Though, oil quenches are far safer. Unless you enjoy losing half of your blades.
some makers quench in warm water for only two seconds, then into oil. friend of mine hardened an 8670 blade in 140 degree water, using an interrupted quench. it worked, but 8670 is a little more hardenable than plain carbon steel.
Great work, but my suggestion is- start tempering maximum 2 hours after quenching, don't leave it 'till next morning. Otherwise- all hardening stresses within steel will become permanent. The blade will be hard, but brittle, not so tough. After quenching changes within steel are still ongoing, so- it would be perfect to start tempering immediately after quenching. Then- same hardness as on next morning, but- more toughness.
After one hour of tempering, let it cool slowly- it will become more impact resistant and tough.
Would be interested in seeing how to straighten out any curves. Too many times have my blades developed curves and I'm not sure how to mitigate it. Love the videos btw :)
My technique has been to letting it cool between 2 pieces of wood after the 2nd quench, just be careful, if its a long piece dont put a small weight in the middle it might crack your blade, i use concrete blocks that i made and they work quite well, 2 40 lb weights on the ends and a 20 lb in the middle. leave it over night and you're generally good to go
@@emanresu8968 that’s a great idea! I’ve heard of some people straightening during tempering, but not between quenches (btw, is there a benefit to doing more than one quench? I’ve only ever done a single quench in oil)
I have made a set of tools which are made from straight bar with a U shape on the ends. By pulling my hands on the x axis >< or outwards you can quickly reduce any curves sideways and also any corkscrewing in the y axis.
These videos are super cool and helpful as a beginner getting into katana making thank you for the helpful and informative stuff!
I thought it was better to use oil instead of water to quench because water leaves the metal brittle? Is it more about the speed in which the metal is cooled rather than the liquid in which it is cooled that determines the metal's quality?
I am making preparations to begin a local blacksmithing business so I want to make absolutely sure that I have all of the information I need from more experienced blacksmiths before I begin.
Japanese bladesmiths traditionally use water. Since I make Japanese-style blades, I generally try to follow their process.
Regarding brittleness, there are many, many factors to consider, and I don't pretend to understand all of them. Water quenching is usually more of a shock to the metal than oil, which makes it more likely the blade will crack during quenching. If the blade doesn't crack, then when you temper it you reduce the brittleness, and after tempering brittleness isn't a problem. In my experience, water quenching produces a nice, bright hamon, but other people have commented that water quenching may produce a deeper hardening which can actually reduce the hamon. So... I don't know. I need to test that theory for myself to see how it works with my steel and combined with the rest of my process.
Yes, I believe that brittleness is more about the speed of cooling than the liquid used. In this, water and oil are VERY different. Water cannot get hotter than its boiling point and still remain a liquid. Water vaporizes on contact with the very hot metal. Oil can heat up to hundreds of degrees, and then it bursts into flame. it doesn't form the same kind of vapor cloud around the metal like water does (certainly not at the same temperatures). These are only a couple of the ways in which water and oil are different.
I think whether you choose water or oil depends on what you're trying to accomplish. Lots of knifemakers use oil. For now, I still prefer water.
@@oldpuebloforge I saw some people quench their blades in water by dipping part of it in, but taking it right back out, waiting a second or two, then repeating the process. I can only guess that they are also controlling the cooling speed so that it doesn't become as brittle. I guess we will both have to experiment with different quenching methods.
This is awesome man I’m so glad I found this. Is the water you’re using just tap water or distilled or anything special?
Tap water. Nothing special. The thing that matters is temperature.
Thanks for the compliment on the videos.
You can add salt and make Brian solution for quenching bro
@@oldpuebloforge 👆
Interesting. I always quench my swords with fresh blood from a condemned man. The finished blade is then named after his mother.
what about if... if the blade is not straight enough, after quenching.
what should we do?
My blades always warp a little during the quench and they always require a little straightening. (I'm talking about lateral warping.) This is normal. It is easiest to straighten them when they're hot. So, I temper them at 400 Fahrenheit (in my oven in the case of small blades) and immediately straighten them while they're still hot. You can straighten them by putting them in a vise and levering them with tongs. You can even do a little hammering along the spine edge. Just don't hammer the cutting edge, because you might break the blade.
Basically, you just bend them a little until they're straight. You must be careful not to break the blade. But it is common for blades to warp during quenching, and some straightening is always required.
Can’t wait for the next one
gasバーナーによる焼入れですね
海外では良い炭が無いのでしょうか⁉️
炉が短く全体の刀身に上手く均一に焼入れが出来たのでしょうか？
実戦刀では元にそれ程焼きを入れる必要が無いので、刀身の焼き色を見ると先から３/４辺り迄均一に焼いて居るようですね
日本の刀匠で修行されたのでしょうね
Nice presentation, I like your videos! I'm working on a katana for a customer, my first one so I'm gathering all the info I can. I'm using W1 and have been planning on an oil quench because I couldn't prevent it from cracking in small scale tests when quenching in water. I didn't heat the water or interrupt the quench, so I'll have to try that out. What kind of failure rate do you see with this method? Even if I can make water work in a test I may still do oil as I literally can't afford to have this blade fail, but next time . . .
I have a fairly high failure rate. Maybe 1 in 5. I do it this way anyway, because it produces a brighter hamon.
Sir, how could we temper 1080 without oven after water quench. Because i have no oven. How could I temper on my furnace, could you suggest me how to do simple way tempering and farenheit degree
Do katana curve when they are quenched only if they are straight? What if the Katana is already curved? Doesn't it curve?
If already curved, it curves more.
@@oldpuebloforgeAssuming ninjato would have been made the same way as a katana, would they have to be reverse curved before the quench to end up straight after the quench?
Thank you for this video
I'm very happy that you liked it.
I've seen other differential hardening videos where the sori produced by the quench is quite substantial. Do you know why the added curve in your blade is so slight compared to others? Thanks :)
Is this type of heat treatment possible - with this beautiful end result - with smaller and thinner blades +/- 2.5~4 mm thickness?
Absolutely. But... this does have a higher risk of cracking than oil quenching. So keep the cutting edge thick. 2mm minimum.
Hello!! Do you do the curve before the quenching or the traditional way works in modern steel too?
Do you keep the water at room temperature?
The idea that traditional katanas got their curve entirely from the quenching process is a myth. They did curve some during the quench, but they were forged with some curve to them, too. My process is similar to the traditional Japanese process, and I get similar results. The water is about 120 degrees F.
@@oldpuebloforge Thank you!!! your videos are very helpful!
@@oldpuebloforge wait really? I never knew it was a myth wow
Hello, question ❓ would you or have you quenched 1095 in this fashion with 1095 in 120 degree water? Thanks for the great informative videos sir.
Yes, same exact process for 1095
Greetings from finland, great video. I have a blade i would like to quench and temper, i am unsure of the material and afraid of it cracking. Would it be safer to quench in oil or water with intervals, im not so concerned of the hamon.
Oil is definitely safer.
@@oldpuebloforge alright, thanks for fast reply 😁
How many days later is it better to re-tamper with clay?
I'm sorry, I don't understand your question.
@@oldpuebloforge i mean
How many times can a sword be tampered with clay?
Would tampering once a year be good for a sword or once a life?
The hardening of the blade change de micro structure of the steel, so you just have to do it once
@@pedrobarros9032 thanks for your good advice
What would happend if you quench the katana in oil?
Oil quenching works perfectly well. Less of a shock than water. Less likely to crack. Hamon not quite as bright or detailed.
@@oldpuebloforge Do it will bend like the water quenching?
Wow this is great. I would just like to ask something. How high is the chance of cracking if you have the right temperature of steel (850 degrees C) and a high temperature of water to avoid thermal shock? Because i am aware this can cause cracking.
The chance is relatively high. I crack maybe 1/4 of my blades. There are ways of dramatically decreasing the chance of cracking. One is to only quench for 4 seconds, then immediately transfer to hot oil tempering. Immediately. Do not continue to quench until room temperature.
4 second quenching plus immediate tempering. The blade rarely cracks. Almost never. But the hamon may not be as nice.
@@oldpuebloforge ok thanks for the tips. But if i dont have the resources for hot oil? Would quenching for 4 seconds in the boiling water and then going onto immediately tempering in the forge to the needed temperature work just as well? Also this will be my first quench
@@blacktemplar2207 I have never tempered in a forge before. I cannot give any advice about that.
But if you quench for only 4 seconds, it is less stressful on the blade than what I normally do.
You could try quenching for 4 seconds, waiting for a few seconds, then quenching again for a couple seconds, then waiting, and so on. Quenching in intervals to avoid cracking.
@@oldpuebloforge Ill try that. when i said forge i pretty much meant just a place that can get hot enough to heat steel to a red colour, whether that be a full on forge or a campfire. But i will try doing this method of quenching. Thanks for the info 😄
Remember, quench at 850 C, temper at 205 C. You can temper perfectly well in your kitchen oven if it's big enough.
I'm not that brave. I've got a 25" one also out of W2 I was gonna do an interrupted water then parks 50. If you did it that way how long would you leave it in the water to not get the reverse bend in the parks
Sorry, I couldn't tell you. I don't have experience with that method.
Very nice work, btw.
Thank you!
What is the purpose of quenching
It hardens the steel. Unquenched steel is relatively malleable, and it doesn't hold a sharp edge. All knives and tools of all kinds are made of steel that is quenched and hardened in some way.
Nice, that was interesting
Thanks!
3:35 sorry this clay, can reuse?
@@debung1998 No.
刀刃包土淬火建議水倒1公分高即可刀刃部份淬火刀背部伤不要沾到水
High risk high reward, subbed.
Thanks!
What steel do you used for this katana. I used 5160 leaf spring steel, so i applied only furnace cement not making hamon. Please help
5160 heat treats differently. It is an oil quenching steel, I think, and it will not make a good hamon. Not the right kind of steel. Watch my video series from the beginning. You will see what kind of steel I use. It is W1 drill rod. I now use W2 bar. It is clean, plain, high-carbon steel. Like T10, 1095, etc.
@@oldpuebloforge Thank you for replying sir. Only i have leaf spring steel here. I can't see 1090 carbon and others. Where could i find good carbon steel from material? Is weight lifting rod is good enough for katana and making hamon. It's alloy steel from Amazon i see. Because I'ved purchased furnace cement from amazon.in, i don't want to waste it without use for hamon.
I am from indonesian
Can you tell me. What is material to make clay?..
Furnace cement
Thanks you mr
Love it new sub keep it up
Что за жидкость при отпуске?
Hey there! The same guy that commented that is making his own katana here.
So, I don’t have a specialized tool for the oil bath myself, what do you suggest I should do?
Thanks for your video, you’re a huge inspiration for me to get into the world of blacksmithing.
I didn't have an oil bath thing either until I made one. So, that's what I recommend: make one! You can do it! It's a pipe inside another pipe with ceramic wool insulation between them. That's it. If you can make a katana, you can make an oil tempering rig. I don't know what I would recommend otherwise. I temper knife blades in my regular oven. But a katana is too long to fit in there.
Have you made any Japanese style blades before? If not, I don't recommend that you start with a katana. I recommend that you start with a tanto (dagger). That will give you the chance to practice on something a bit less complicated to start with. Also, it will give you the chance to begin acquiring tools. You don't need an oil rig to temper a tanto. You can just use your kitchen oven. I strongly recommend that you make a few tantos before trying a katana.
@@oldpuebloforge alright, will do!
@@germanr7118 So how did it go?
Brilliant 👍
Thank you!
Amazing video! Can i ask what tipe of oil do you use for the tempering?
Thank you! I use peanut oil. It doesn't flame up easily. Less fire hazard.
@@oldpuebloforge oh ok! Thanks a lot. Can i also ask if you change it and how often?
@@eliasilvestri8236 I haven't replaced it in years. I just keep adding to it. Maybe I should, though.
Did you first cover the knife with clay?
Yes. Please see my previous video
when is the next video coming?
Should be coming soon. I'm trying to figure out how to photograph the hamon so it looks right.
Can't Wait for next process
Subscribed
What's the last procedure for?
Placing the blade in hot oil for an hour is called tempering. It decreases the brittleness of the blade making it tougher and more shock resistant. Other people temper in an oven, a fire, a forge, or other ways. I like the oil because it gives me very tight control over temperature.
@@oldpuebloforge thanks
What kind of oil do use for the temper bath?
Peanut oil.
to make clay, as in the video what materials are needed
Furnace cement, red iron oxide, water.
Mucho gusto...
What Kind of Steel was it
W1 drill rod.
@@oldpuebloforge THX, wow
Did you put the clay on both sides?
Absolutely.
How did you go about making your oil bath?
It's a pipe inside a larger diameter pipe with fire proof insulation between the two pipes.
Sir blade apply chemical name
1095 or better 1080 or 1060 carbon steel???
Any of these can produce a good sword.
@@oldpuebloforge Please one more question. 1080 could making process good hamon along with water quench???
Great process.....btw.. Blade material?
Thank you! The blade is made from a 12" long piece of 1.25" diameter W1 drill rod. Please see the first video in this series.
@@oldpuebloforge oh yeaaa..already watch the first forging....can't wait polishing process....BTW have you Made from spring steel / 5160?
I have never worked with 5160. For katanas I only use plain carbon steel. 1075, 1080, 1095, W1, W2.
@@oldpuebloforge thanks for the sharing
Do you sell made swords?
Sorry, I don't. I give them away as gifts to friends and family.
I sell steel that you can buy to make knives and swords from.
I thought you quenched in oil?
You can. But Japanese swordsmiths traditionally quench in water. I think it depends on the grade of steel, too. Plain carbon steels quench well in water.
@@oldpuebloforgeis it good to mixed salt with water?
First comment 🎉
заготовка изначально как была кривая, так такая же осталась. нет искривления при закалке.
Я часто предварительно изгибаю свои лезвия, потому что мне нравится, чтобы они были более изогнутыми, чем можно добиться во время закалки. Поверьте, лезвие изогнулось во время закалки.
Fire melts a sword water cools the sword and creates steam.
Ghost of tsushima brought me here
I wonder, what would it take for you to teach this to people?(let's say 16 year olds)
I have taught a couple of people. One was a young man in his late teens. But you don't need private lessons. Just watch my videos. It's all in there.
@@oldpuebloforge that's awesome... I would love to be thought by you... if you lived a little closer lol
heard water and immediatly paused the video so i didn't have to see any more of it.
I follow a mostly traditional Japanese method. Japanese swordsmiths quench in water.
.the blade already has a curve before it quenching...
.this is failure... 😂
Virtually all Japanese blades are forged with some curvature. The heat treatment increases the curve, but it doesn't create the curve from a blade that was forged completely straight. In fact, when oil quenching a differentially hardened blade, reverse curving occurs during quench, so the blade has to be forged more curved than you want the finished blade to be.