Stainless steel khukuris now shipping... Huh?

Bri in Chi

Bri in Chi

Joined
May 28, 2003
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It seems... Got a little un-signed Dhankuta style Bilton as a forum special, and decided it might look better with a nicely mottled patina. I scrubbed the blade with detergent and fine abrasive, and then applied some deli-style mustard, wrapped it in plastic - and settled down to watch a movie. About half-way through the flick, I checked the blade out - nothing happening! I then applied some fresh lemon juice and Tabasco to accelerate the reaction. A thing that always worked in the past. At the end of the movie, virtually no coloring had occurred. The blade looks about like it did before the treatment. Like almost brand new. A few very light stains, but no real patina. What is this blade made out of...440? :confused:
 
Yangdu said:
Biltons are made by Dharan local shop Kami.
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Hard to control a shop/kami elsewhere.

Have you checked the hardness along the edge?


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Bri in Chi said:
What is this blade made out of...440? :confused:
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If the blade is hardened at all, it probably isn't stainless. Stainless is harder to heat treat than the 5160 that the kamis normally use, and I don't think the kamis would be able to sucessfully harden it. They would probably just use the normal method and it wouldn't work.

In addition, considering the source of the steel (probably a scrap pile), I doubt that it would be a high-quality stainless suitable for knife blades.

I guess you could also try putting some bluing compound on the knife. Or soak the blade in vinegar and see if that can etch it.
 
When I read this thread...something pinged in the back of my mind...it sounded so familiar...

maybe this is an explaination for what is going on...maybe not...

When I was at the ABS Blade school I forged a recurve shaped blade from 5160...it was maybe 7 inches long...Chalie Ochs was showing the class how to use water to quench blades...so I decided to give it a try...I got the blade hot...and slowly lowered it point first into a five gallon bucket of water...after a few seconds...pulled it out...waited a second and then put it in until it quit hissing...why it did not crack or warp I cannot say...

I didn't do anything else with it until I got back to Wyoming...the surface was covered with a "very shiny" bubble pattern that happens sometimes...I took it to the grinder...dadgum belt would not cut the surface of the steel! I wore out a couple taking off that intial shiny layer...I finished it out...and etched the blade...there were a couple places that still showed that shiny layer...the rest of the blade etched normally...but what was interesting was that the remaining shiny layer was HARD!(you could not cut it with a file!) but that the part that etched was soft as butter...

oddly enough the part that did etch...did not showed the same grain pattern as what I normally see with 5160...it didn't show the refinement of a quenched steel...

I still have that blade in my junk bucket...

If I had to venture a guess...I'd say that is what happened to your piece...that shiny surface is hard as hell...it will be tough to etch with simple solutions...it may even be hard to scratch with abrasives...

No telling what is underneath that first layer...it may go all the way through I spose...only way to find out is etch with ferric...(never tried vinegar) and see what you can see...

Could be this other shop was using the bucket method or has not perfected the "teapot" method of quenching with water...

If you test this blade as is...it will prolly cut fine...I would bet though as you sharpen down into that hard layer you will get to softer steel...just a hunch...
HT with water is a tricky business at best and done by Masters...is a thing to behold...done by three thumbed jack holes will give sporadic results and failures...

I can't think how a guy could tell if he had it right...just by looking at the outside of the steel...after it is polished...no way to know if you got it right...

That is why I etch everything that comes out of the shop...the etch don't lie...

My guess is you got 5160...or some type of spring steell with chrome in it...but that the HT wasn't a 100%

Shane
 
Hit it with the ferric. If that won't etch it, try rust remover. Nothing can resist the rust remover. When you do get it etched, I'd love to know how it looks.

I'm fortunate enough to have two Dhankutas and I etched both yesterday. They did take a bit longer to etch than usual but it wasn't particularly difficult. (I only use PCB etchant these days.) The hardened areas looked good. What was interesting, though, was the patterns that came out of the steel. It looked almost like pattern welded and sort of "rolls" away from the hamon. Odd. I doubt that I'll be able to photograph it without a macro lens but I'm going to try. None of my other khuks (or swords, for that matter) look like this.

I'm not a metallurgist and don't know the first thing about it. All I know is that these Dhankuta pieces have something unusual going on with them. Perhaps one of our more learned forumites can tell us exactly what's going on here and why.

Shane - interesting story. Do you know exactly what happened to that blade?
 
Satori said:
What was interesting, though, was the patterns that came out of the steel. It looked almost like pattern welded and sort of "rolls" away from the hamon. Odd.
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Sounds like alloy banding - a lot of knifemakers will refer to this as "grain" in the steel. You get areas in the steel where the alloying elements have separated out into bands, this gives the pattern. Take a look at some of the thermally cycled 52100 blades that people post over in the makers' section.
 
When I wipped it down with denatured Alcohol and hit the blade with B. C. Super Blue, it colored right away. Perhaps there is some secret mustard-proof treatment being applied at Bir Ghorka? Oh, yah. That must be it. :confused: Also tried a file on the edge, and it skated right across. Wouldn't bite at all. I think this might be my new hot dog knife. :D
 
Bri in Chi said:
When I wipped it down with denatured Alcohol and hit the blade with B. C. Super Blue, it colored right away. Perhaps there is some secret mustard-proof treatment being applied at Bir Ghorka? Oh, yah. That must be it. :confused: Also tried a file on the edge, and it skated right across. Wouldn't bite at all. I think this might be my new hot dog knife. :D
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Gentlemen, we have a wiener. :p
 
Guys,

If I knew what had happened to that blade...I'd sure feel smart...

If I tried to describe it using my very weak metallurgical vocabulary...I'd prolly use them wrong and some Metal Honcho would blast me out of the saddle...

I could just as easily say it was Gremlins...or worse yet Shop Gnomes...(I hate those guys...always hiding my tools!)

Sorry I can't give a more professional opinion...

I was just trying to help...prolly just confused matters...

Shane
 
I went out to the shop and found that blade...

I tried to scan it...but could not bring out the effect...

If anybody wants to look at it...I'd be glad to mail it to them...

SHane
 
shane justice said:
I was just trying to help...prolly just confused matters...
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Not at all. We have a bit of a mystery here and additional opinions are more helpful, not less so - especially from someone with some experience in the area such as yourself.

KM - that may be it. It's all Greek to me but that makes sense. I gave one of them away as a gift after I did the etches and took pics; the one that I kept has one of those cool metal handles and wasn't intended to be a user but I'm planning on putting it through its paces now. Both seemed to have the proper hardness and both took an excellent edge.

Regardless, it's a very striking look and something that I wasn't expecting.
 
Sorry been out of town for a couple of days...

Dang....I looked back in my shop notes...and can't find this one...

I think I did it down at the school...in their toaster oven...

My memory is gone...I forget where I leave my reminder notes these days...

Let's say I did it...prolly where eveybody had it set down there...for 350 degrees F...for prolly one shot...that was the way we were doing it...I tink?

Anyway...weird blade...

Good thread...

SHane
 
Bri in Chi said:
: and then applied some deli-style mustard, wrapped it in plastic - and settled down to watch a movie. About half-way through the flick, I checked the blade out - nothing happening!:
Click to expand...

Bri in Chi
When you wrapped it in the plastic was it completely sealed of from any oxygen getting to it. When I read about the mustard blueing I had a kitchen knife that would get rust on it really easy so I tried the mustard blueing on it. I cleaned it up and then applied the mustard and placed it in a ziplock bag. When I came back to check it there was no blueing at all so I left it even longer in the ziplock bag, still nothing. I then got thinking about what cause it to blue. I realized that without any oxygen in the bag the chemical reaction would not work so I took it out and then it blued pretty fast. Maybe this was the problem you where having.
 
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