Water Quenching- My Experiences

LongRifle

LongRifle

Joined
Apr 5, 2000
Messages
2,018
I've spoken with a few members here about hamons and how much I enjoy working with them. I've decided to start doing more work in the traditional Japanese style, that includes water quenching blades. I've been doing some testing in water; trying to determine what I can get away with and what I can expect.

I wanted to pass a little information on to everyone, maybe it will encourage others to try their hand at hamon or even water :).

Here's the rundown of what I did wrong on this blade ;) and what others should consider when attempting their own quench.

1. The blade was too thin. I ground this blade with the intention of an oil quench. The edge was slightly under 1/16", I've found 3/32 to be ideal.

2. I "corrected" the sori too much; I quenched the blade in oil on the first attempt and got 1/8" drop. I could not correct the curve with controlled heating and some light hammering.

I decided to quench the blade for a three count, remove the blade for five, return to quench, then out. Well, the sori was corrected...over corrected. There is a 1/8" sori in this blade, a combined total of 1/4" curve out of a 9" blade. I'm convinced the long out of quench cooling is the culprit.

3. Keep the blade at a low temperature. I use a long soak and looow heat in the forge to bring the blade to austentizing. The hotter the blade is the more likely it's going to fail. A helpful hint is to HT at night; you can see the blade austentize if you watch closely.

I knew I was pushing this blade too hot, but I wanted to max out the sori...which was stupid. Even at the high heat the temp was still lower than "standard" knife quenching.

4. Be happy with your results. I quenched this blade three times. The first in oil, the second in water, and the cracker in water :). The second quench did not fix the sori, but the results were almost identical; four distinct habuchi, and more activity then I've been able to acheive before. So, instead of letting things be I went for broke, and that's exactly what happened.

5. When oil quenching blades keep the clay as thin as possible; the thicker the clay the more drop in the spine you'll see. Not to mention the spine will remain too soft.

Hopefully that little bit of guidance will help, or at least encourage, some of you to work in hamon.

Here's a shot of the doomed blade and its friendly reminders not to get too arogant :)...I might feel bad if I didn't have two others ready to go :).

~In case you're wondering, this blade was only polished to 220 and dunked in my short ferric tank, I didn't waste too much time :). Also, the thick lines running across the blade are etch lines...

attachment.php


attachment.php

Matt
 
1065, 9" blade, 13" OAL, 1/4" at the thickest, tapers to 1/16" at the point...way too thin :).
 
What do you use for clay?
A while back I quenched a clay coated blade of W1 in water. The hard part almost completely sheared away from the soft part. :D
 
I use satanite mixed thin for the clay. I apply a skim coat to the entire blade, then the back, then ashi. Having a blade shear in half sounds pretty cool, almost worth the work :).
 
I retrospect it is, but at the time I was pretty disgusted. :D
Does satanite stick better than furnace cement? I always have to wrap it with wire, or the clay comes off in the forge.
 
I've never tried furnace cement, so I can't comment, but I have never had a problem with satanite falling off. Make sure the blade is washed very well and the finish isn't too high-120 grit.

I'm trying to motivate myself to forge a wakizashi this afternoon, however the couch looks pretty nice :).
 
Oh young grass-hoppa'.... already trying to snatch the pebble...


HA!!! :D :p

I messed with water for well over a year, and it really does create some whicked things, and the blades get screaming balls hard.

But even once I got "confident" with it, I was still breaking about 4 blades out of 10, and that drove me crazy. I talked with the Kapps, and they said Yoshindo's success rate is usually around 70%, and that that's one of the best success rates of the Japanese smiths.

So if I was really awesome I'd still break 3 out of 10?!?!?!? Yikes.

I'd probably keep pursuing it if I was in your position Matt. Having to finish and sell at least a couple, I quit messing with it.

BTW- I hate you more, because now I'm probably going to be stupid and go try some again!

Oh, just for S's&G's... I would do LOTS of descending thermal cycles in my salt, then clay coat. Then I would put my thermal cupple from the salt bath into a pipe inside my forge, and run my forge around 1400-1425F, long soak, (at night like you said) and quench for 3 seconds in, 2 out, 3 in, 2 out, 3 in, and then run like hell to the oven.

I wish I hadn't thrown most of the scrap away, I had one that- WHILE I WAS LOOKING AT IT, pulled itself apart right at the line, and then sheared down to the edge. The point pulled back about 1.5" when it did that. Sort of a "flip-top" blade :eek:

I like you post a lot Matt! :D
 
I'll stick with my oil. Everyonce in awhile I'll think about using water but after using it I know its not the way for me. I even went with a brine on a few blades a couple weeks ago. The blades didn't crack but they wern't very strong and would break very easy. Haven't been doing much clay lately but have had good luck winding alittle steel wire around the blade to give the clay something to stick to.
 
Ray, I found the water quenched blades I did to be the toughest and best cutting... but you have to increase the tempering temp A LOT. They get a heck of a lot harder in water than in oil, and if you use the same tempering temps they'll be a brittle as a file.

Water still makes me nervous... and I like my oil :D
 
You guys have bigger balls than mine apparently. I have played wit water only a couple times and they both went ping, pang, pow! I cant afford to lose blades like that but it sure is cool if it works I bet. The w2 is more forgiving isnt it? Would the temper on it need to be higher too?
 
Nick, That may have been it. I ran the same temp cycle as if I had used oil. Water makes me nervous also. When I did the warm water quench there were no pings but cracks after I did some grinding. The cracks you hope are just a hair and then you see it on the otherside. I'll stick with my oil.
 
I've never tried furnace cement, so I can't comment, but I have never had a problem with satanite falling off. Make sure the blade is washed very well and the finish isn't too high-120 grit.
Click to expand...

Could this be your very problem? The few makers who I've seen post about this kind of thing in detail say they used to use 120 or 150 grit then switched up to 220 or so and this helped control cracking.
 
Good question, but I don't think so... I had several at a 400x finish crack and was most successful stopping at 60X or draw filing giving a "grippy" surface area for the clay.

I think it really comes down to time and temp.

But I might be all wet :foot: :D
 
Well, here goes.

I have never cracked a blade in water. (Probably will crack the next 10 or so:) ). I also do an interrupted quench that begins with a very short 3 count in 100 degree water (thanks Wally Hayes). I have only tried brine once a long time ago (thanks J.D. Smith), but think that that may really be the way to go--faster and potentially safer, who woulda thunk it? That said, I have never done anything over bowie length either.

I am with Matt here as far as thickness is concerned. Leaving some meat on the edge makes all the difference. And if the entire idea is to reduce hardenability through thermal cycles, followed by controlling hardening with clay, the extra thickness is not really an issue.

On swords I have to think there is a lot more room for horrible tragedies. But even guys like Yoshindo are using charcoal and eyeballing it--that has to detract from their success rate as well.

As Nick, I am using a thermocouple and maintaining tight temps. Basically my limited formula for success is due to the advice of a lot of great guys--including Matt and Nick above--such as Wally Hayes on interrupted quenching in his videos, Randall Graham on longer soaks at lower temps on the net, and then Don Fogg, Kevin Cashen, Howard Clark, et al. who give great advice everyday to those willing to listen.

Oh, yeah, and run don't walk to your preheated tempering oven/bath/etc.

John
 
Great post John! THANKS very much for mentioning Randal! I meant to put the link to his page on water quenching in my post and spaced it. You've never cracked one in water? DAMN! :cool:

I wouldn't have known squat about getting started with water had I not read Randal's advice about a zillion times.

And Wally makes water quenching that sword look like walking out to get the paper! :eek: VERY nicely done! :cool:

Here's the info so generously shared by Randal Graham.

http://www.dfoggknives.com/waterhardening.htm
 
John, thanks for the tips! Nick, I remembered reading that article before, I'm glad you posted it. Re-reading it gave me a little more confidence to try again :). I've got to get some things in order for Blade before I do more water quenching...maybe in a couple weeks I'll toss another tanto into the drink :).
 
You must log in or register to reply here.
Back
Top