sharpening the JKM-1?

M

Mochiman1

Joined
Aug 23, 1999
Messages
449
one of the fun things about the JKM-1 is the air of mystery surrounding it. The designer is no longer with us to answer questions such as how to deploy the exotic dangler sheath. The builders are half a world away. So I'm left with a couple questions to pose to my fellow fans of this beautiful knife.
I know JKM had in mind a Finnish puokko/Nepalese karda synthesis. And because I once bought a puokko from him as a present for a friend, I know that one of the things JKM enjoyed about puokkos is that they lack a secondary bevel, instead featuring a flat grind tapering down to the edge. That's not the same as a convex edge, right? And I recall JKM saying that the traditional way to sharpen a puokko is to lay the blade pretty much flat against a sharpening stone and then...after that, I forget. Either pass it over the stone with the edge trailing, like in stropping, or the opposite. I passed the info on to the puokko's recipient and promptly forgot the details.
One of the interesting things about turning 50 is the weirdness of eyesight. I'm looking at my JKM-1, and I simply cannot tell if there's even a secondary bevel. I could root around looking for a magnifying glass, but I thought instead I'd just pose the question to the other couple dozen or so JKM-1 owners: is there a secondary bevel? Uncle Bill, do you recall whether JKM provided detailed guidance of that sort to the kamis? And if there is no secondary bevel, like for a puokko, how are you folks sharpening this knife?
 
the mystery endures. could any of our young hawk-eyed jkm-1 fans shed light for us who are weak of eye? be sure and print your reply in GIANT BOLDFACE
 
Jance, at 49 I now keep a magnifying glass on my desk.
wink.gif
My JKM-1 did come with a secondary, edge, bevel. This may upset folks who are enamoured with its mirror finish but, IMO, it's designed to be a user. I decided to eliminate the secondary bevel and sharpen the blade the traditional way by laying the primary bevel flat on the stone. Actually, I started with a bastard file for faster material removal & then moved to a diamond stone as I got closer. I am almost finished with the first side & will post pics whenever I finally finish it.

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Cheers,
Brian

He who finishes with the most toys wins.
 
Brian--when you lay the blade flat against the diamond stone, do you then slice forward into the stone or go the opposite way, as when using a strop? And what are the advantages of the traditional secondary-beveless edge you're creating? I recall JKM used to be enlightening on this subject, but that was awhile ago, and my eyesight is not the only thing that's fading.
 
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Jance when first sharpening one of these with a double bevel it doesn't matter which way you stone the blade.
I personally like a circular motion until almost finished with one side and then the other.
Actually the circular motion can be used to the finished edge, you just get lighter and lighter with the pressure of your strokes which you have to use anyway whether edge trailing or not.
And of course finer and finer grit hones.
This is where the flat diamond hones come in real handy!!
When anyone is not used to putting on an edge with no secondary bevel it is very tempting when you are almost finished to strop the burr off.
Your knife will still be very, very sharp, probably sharper than any knife you've ever owned, and yet still not be as sharp as it can be without the secondary bevel.
I speak from experience on this and you will be surprised just how much further you will have to stone to get rid of that stropped edge!!
frown.gif

Oh and that lightly stoned circular finish is very pretty or at least it is to me. It reminds me of an
"engine turned" finish.

I have a Finnish Puukko that I have almost completed restoring the original edge on that I have worked on over the last couple of years once in a while and it has taught me a lot.
smile.gif


My JKM-1 came with the secondary bevel as well, but now you've got me to thinking.
smile.gif

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>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website

[This message has been edited by Yvsa (edited 11-20-2000).]
 
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Another interesting thing about my Finnish Puukko is the way the handle is designed. No matter which way you lay the knife down the design of the handle butt automatically raises the edge to about a 40º angle off the surface. This will always prevent the edge from being damaged by laying it on a hard surface that might nick the edge.
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I used to think it was kinda stupid as it makes you pretty vulnerable to being cut with its edge in the air like that and then one day it dawned on me. The people who designed and use these knives know how to properly use a knife and to protect its edge, and similar to the Nepali People who are raised with khukuris these people are raised with the Puukko and Leuku!!
Now I think it's pretty dayum-ed neat!!!
smile.gif

And this is another knife that like the khukuri has been around for a long, long time as well and has all the bugs worked out of it!
I don't know about some of the newer designs of today though. I have seen a lot of them without this style handle.

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>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website
 
Yvsa, when you said, "I speak from experience on this and you will be surprised just how much further you will have to stone to get rid of that stropped edge!!" what did you mean by a stropped edge because at that point the edge would not have been stropped. How does a "stropped" edge differ from a regular edge obtained just with stones or ceramic rods?
 
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Steven I used the strop to take off the very fine burr left on the edge and kinda got carried away with it and stropped to dayum-ed much.
That "rounded" the edge enough that further honing was needed to bring it back to flat and it took more to get it back to flat than I would've imagined. However it was still pretty sharp.
smile.gif

You can say I had a very small convex edge instead of the single bevel edge I wanted.
Believe it or not the single bevel edge is much sharper and makes much smoother push cuts in wood. There is very, very little pressure on a single beveled edge.

------------------
>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website
 
Jance, since I'm still at the point where I'm trying to establish the single bevel, I am moving the file & stone both toward & away from the edge. Yvsa's circular method should work great but I find that I have better success holding the angle freehand if I simply go back & forth while moving the tool up & down the length of the blade. Once I have a consistent burr, I'll switch to sharpening away from the edge only.

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Cheers,
Brian

He who finishes with the most toys wins.
 
Another question for Brian and/or Yvsa: when you remove a lot of metal from the edge, such as when you're taking the blade down to a single bevel from a double bevel, aren't you in danger of taking off the tempered layer of metal and thereby leaving your edge softer and less durable? Is there any rule of thumb for how much metal you can safely remove from a khuk? How do you know when to stop? It seems to me that you could actually ruin a blade by sharpening it too much.
 
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I haven't etched my JKM-1, but I did etch one of my carved handled Kumar Karda's and the blade is hardened quite high and will last a hundred years. Steven if there's any doubt you can get the Ferric Chloride from Radio Shack and etch your knife.
I rubbed mine with some fine Scotch Brite after the etching and I love the satin finish with the temper line revealed.YMMV.
smile.gif


------------------
>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website
 
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Chris I got some PCB Etchant at Radio Shack, it contains the Ferric Chloride.
Use a Glass or Plastic container and rubber gloves. I mixed one capful of the etchant to two capfuls of water and then used cotton balls to
"wash" the blade. Don't get any on a stainless steel sink, because it will etch it as well. My dear wife didn't holler at me for doing it though.
smile.gif

The etchant will turn the blade dark and will etch the softer portions a darker color, but you may not see that until you use steel wool or Scotch Brite to clean the blade. You can etch the blade until you get the desired results so don't give up if you didn't let it set long enough the first time.
Wear Safety Glasses or Goggles!!!

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>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website
 
Thanks Yvsa. I think I remember you saying once that Broken Arrow acid etched his Barong in addition to blueing it? Do you know how he did it? Did he etch it first and then blue it, or was it the other way around? I'm curious because it sounds very interesting and maybe something that I want to do to a couple of khukuris, to personalize them and make them all mine. Broken Arrow, any tips?
 
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You're welcome Chris.
smile.gif

BA is the best one to answer your question and an e-mail will surely bring your answer, or you could alert BA to this thread so everyone could see it and it would then be archived for all time and available to all.

I think that BA said he used some Brownell's Blueing splashed on while the blades were still wet with the Ferric Chloride. I know that I really liked the finish as it was very unusual and to me had the effect of making the blades look like well cared for antiques.
smile.gif

And the really cool thing about this finish is that no two knives will ever come out the same.

------------------
>>>>---¥vsa---->®

Each person's work is always a portrait of himself.

---- Samuel Butler.

Khukuri FAQ
Himalayan Imports Website
 
Hey guys,

On my work out Barong I applied the ferric chloride and let it set for one day (24 hrs.). This turned the blade some what dark gray/olive drab. I rubbed some baking soda on the blade and rinsed it off. I then, took some 0000 steel wool to it. Next, I took some Flitz metal polish and polished the entire blade. This evened out the color. I then degressed the blade and ran hot water over the blade. Make sure to wipe off the blade and then apply the cold blue solution. You can use Brownells or the Birchwood casey stuff. Let the blue solution sit for 1-2 hours and rinse the blade off. Dry the blade once again and re-apply some more ferric chloride on the blade. Let it sit for an addittional hour. Last, clean off the acid and ake some steel wool and Flitz to even out the patterns.

Hope this helps. It takes some time to do this, so don't rush it. Start when you are fresh and have energy.
 
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