Heat treating Q for Art S.

S

stevomiller

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May 4, 2001
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Hi Art! Had a question you might be able to answer ~ will the kami's teapot method of quenching work with a simple medium carbon steel such as 1050/1060? I could be wrong, but my gut feeling is that it might be too slow of a quench. If so, do you think that the teapot method came about because of the use of 5160 since it is faster quenching? Thanks for your reply, stevo
 
Stevo,
The kami's method should work, if you adjust the rate of flow for the particular steel you're quenching. A 10-series steel would require a slightly faster quench, so you want more water; maybe a coffee pot instead of a tea pot.
Unless you're quenching something with a very thick spine like a khuk, there will probably not be enough residual heat to temper the hardened edge. You'll want to use an oven or other heat source to temper the blade.
The kamis have developed methods that work very well for them, but the kamis also spend years learning to get predictable results with those methods.
The methods are interesting, but I think you'll get better results with fewer headaches if you stick to methods more widely used here. A straight oil quench or interrupted water quench is a lot easier to learn.
 
Thanks for the reply, Art. Oil quench is what I'd always used for HC and alloy steels. I agree that the two for one (quenched edge/residual heat temper) would be very tricky to pull off on anything other than a chisel. There must be a heck of a learning curve to it!
 
I don't know how succesful you could rate their success. Under what terms?
I have taken four old Kuhkris and three brand new ones; acid etched them and rockwelled them. The results are inconsistent and in the overall - simply deplorable.
Of the three latest ones the larger one had almost no temper whatsoever. Its 16" inches of pearlite (unhardened steel) exept for a barely 16th inch band here and there running on and off the edge. The m-43's had a spot three inches long and 1/4" high on the striking part with the rest of the blade unhardened including the point.
The other had barely any temper at all and the point and leading edge rolled.

I have been smithing for almost thirty years. I have smelted my own steel, I make Japanese katana, as well as other products.
In regards to the abilities to handle steel well in native kukris?
I am speachless.
They are missing enormous potential in the product they use. A simple quench and forge temper would be easier to do and produce a F-A-R superior product.
Too bad-a couple of days of quenching and grinding lessons and they would have a world class product for very little-if any- increase in cost.
It appears their market base doesn't know and doesn't care.

Dan
 
Have noticed differences on khukuris(new ones). But overall the sweet spot was hardened and the tip and tang were softer as they were intended to be. I think that is the kamis goal.
 
hehehe do I smell flame.:p

Well, I bought 6 bowie knives (makers un-named). Three were old and three were new. I etched them out and there were huge variences (again Im not saying if they were all from the same maker, different makers, etc...). One had only the edge hardened, while the body was all soft. Another was really poorly tempered. American smiths need to learn how to make knives. Too bad the market base that buys American knives cant tell the difference or dont care.

So hows that for a flame war starter.:D :p :rolleyes: :confused: :barf:
 
Originally posted by Dan Harden
in the overall - simply deplorable.
Of the three latest ones
Click to expand...
Very strange.

I have etched most of mine to visualize the zones.
In all cases they have been exactly as expected.
And very clear and well defined.

If your old kukris were tourist products
then no effort at hardening would be expected.
From other sources, who knows.

You don't specify the source of the 3 newer kukris.
If they are indeed from the HI factory then I'm
sure Uncle Bill will replace these under warranty.
Your discription makes them sound defective & atypical.

If the blades are from a different source than HI,
then your comments are irrelevent to the discussion
because there's no telling who, what, when, why, etc.
When the HI business first started many many years ago
they contracted production from a pre-existing factory.
They stopped doing so because they had to reject a large
proportion of the blades delivered due to just such problems.

The teapot method is a proven technique;
when properly done.

One of the reasons we trust HI products
is that we've seen the proof that these kamis do it properly.
That proof is both by using the blades and by etching them.
And sharpening & hardness testing them, to be more specific.

And, yes, as hoghead says, the tip/point is supposed to be soft enough not to chip.

Please clarify your sources for the blades you tested.
If it's one kami's production then we should watch out for his blades.
 
Howdy Dan, welcome to the psycho ward aka Cantina. I agree with both Art and yourself that a traditional (western) quench and subsequent temper is far more predictable and easier to control. Also, a tempered martensite spine instead of pearlite would provide added stiffness/resistance to taking a set. This would allow the use of thinner blade stock without the worries of it becoming bent under hard usage. If one still wanted a martensite/pearlite composite an edge quench or the Japanese clay coating method would be my choice.

In the kamis' defense, though, I seem to have had better luck than yourself. I have a WWII by Durba,2 Sirus by Bura, and an AK by Sanu that I have etched with FC or lime juice. The hardened portion on these encompasses a 5/16"- 3/8" band starting at the forward portion of the recurve and extending to the tip. The WWII and the AK are plenty hard at their tips, the others softer than I would have made them ~ but still ok for their intended purpose.

The gist of my original post was, I guess "Do you think that this is the traditional (pre 1950 or so) method of heat treating a kukri?" Adios, Stevo
 
Forgot this line in my previous post
Originally posted by Dan Harden .....It appears their market base doesn't know and doesn't care. Dan
Click to expand...
Do care, do know.
:D
 
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