Windlass Khuks

Wow! I definitely had the right impression. I can't believe it. How does the Indian Army use that thing? I wasn't planning to buy one anyway, too many HI knives on the agenda.

Can someone please explain Cho creep to me?

And also how do you etch a blade to show the hard areas?

Andy
 
aproy,

When the guys are talking cho creep, they are talking about the placement of that notch put into the blade near the handle. This area is usually called a cho or kaudi, and is usually traditionally placed pretty close to the handle area.
Now-a-days more and more one starts to see that this cho area is being placed further up the blade, hence the name "cho creep". This means that little by little many of the makers of the khukuri knives seem to be allowing the cho to creep away from it's usual and more traditional area of placement.
Since many HI's have a habaki style bolster, they tend to even further suffer from cho creep (having the cho placed even further out because of the extended length of the bolster).

Those photos put up of the hardened area of that Windlass Assam Rifles khukuri are extremely telling and damning indeed, thanks for sharing.

The comments you guys made after the photos were shown, had me laughing pretty hard :)
 
aproy1101 said:
And also how do you etch a blade to show the hard areas?

Andy
Click to expand...

Andy, here is probably more than you want to know about etching blades. :) It's only how I do it. I think Dave Rishar has posted good instructions before too.

Steve


Please understand that there are as many methods to etch blades as there are people that do it. Do a search on etching and read what others have to say.


1. Use acetone or denatured alcohol to degrease the blade. Both are flammable, so use good ventilation and follow the safety instructions on the can.
2. Cut a lemon, lime or other acidic fruit, and rub on the blade. Rub one side, then the other. Repeat until the pattern develops to your liking.
3. Rinse the blade in cold water.
4. Neutralize the acid by rubbing the blade with a thick mixture of baking soda (sodium bicarbonate) and water.
5. Rinse the blade in cold water.
6. Dry the blade thoroughly, and oil it well with mineral oil, or whatever you currently use to prevent rust.

An alternative is to use ferric chloride. It works quicker and sometimes brings the pattern out better, but is potentially more dangerous to the blade.

1. Use acetone or denatured alcohol to degrease the blade. Both are flammable, so use good ventilation and follow the safety instructions on the can.
2. Mix one part Ferric Chloride, available in the US from Radio Shack as Printed circuit board etchant, with 3 or 4 parts distilled water.
3. Using rubber gloves saturate a rag or paper towel with the solution and rub it onto the blade. Put it on with a fully saturated rag, and wipe it on evenly. Do one side then the other, doing your best to cover the full side of the blade in one pass. Don’t let the solution run down into the grip. I use a plastic trough that is used to wet wallpaper that I bought at the local home improvements store to catch the drips.
4. When satisfied with the pattern, rinse with cold water.
5. Rub the blade with a rag or paper towel saturated with vinegar. I’ve read that this helps to stop the ferric chloride reaction.
6. Rinse with cold water.
7 Neutralize the acid by rubbing the blade with a thick mixture of baking soda (sodium bicarbonate) and water.
8. Rinse with cold water.
9 Dry the blade thoroughly, and oil it well with mineral oil, or whatever you currently use to prevent rust.




An explanation why Vinegar is used to neutralize FeCl, by Firkin of Bladeforums:
Interesting discussion. I'll butt in if I may.

Simple protic acid/base neutralization concepts won't work for this system of ferric chloride in water, in the presence of air (oxygen).

The system is actually very complicated. But think of oxidation (as in burning), which is what etching and rusting is.

As I understand it, an approximate summary is that, ferric chloride (also known as iron(III) chloride) can covert to iron oxides and iron hydroxides (rust) in the presence of oxygen and water. This releases hydrochloric acid, which attacks the iron in the blade, making hydrogen, and ferric chloride (and iron(II) chloride also known as ferrous chloride) again.
Repeat the conversion of the two types of iron chloride to hydrochloric acid using oxygen from air dissolved in the solution and continue. .

The actual concentration of acid may never be large enough in the bulk solution to be measurable, or considered acidic. But it never gets used up, as the cycle continues to replenish it. But oxygen and the blade continue to be consumed to make iron oxides and iron hydroxides. As iron hydroxides build up, the bulk solution will become somewhat basic. But corrosion will still continue until it gets very basic.

Masochists may get some idea of what's involved by looking at the summary section of this article on corrosion which describes the role of iron chlorides:

http://nautarch.tamu.edu/class/anth605/File9.htm

What is needed is to remove all traces of ferric chloride and ferrous chloride because they let the chloride ions be used over and over again to attack the blade as hydrochloric acid. So the chloride ions are what make this system so effective at eating iron.

Excess ammonia solution (a base, but also a good ligand for iron ions) probably converts nearly all of the iron chlorides to less corosive ammonia complexes of some sort. And any free hydrochloric acid will be neutralized as ammonium chloride, a salt.

Excess vinegar (solution of acetic acid, but the acetate ion half is a good ligand for iron ions) probably converts nearly all the iron chlorides to less corrosive acetate complexes.

Simple mechanical rinsing effects at work too, of course.

Either vinegar or ammonia, likely effectively no more ferric chlorides. But any chloride salts of whatever type left have potential to start rust and generate some iron chlorides, so rinse well with water. Undoubtably things are more complicated than I describe.

My suggestion:

Use more than one treatment with fresh vinegar or ammonia (some tiny proportion of the iron chlorides won't convert--but a tiny proportion of a tiny proportion gets pretty close to zero). And final rinses with water.

Scrub surface if any thing could be trapped under any crud on the surface.

I don't think that baking soda (sodium bicarbonate) solution will convert iron chlorides to alternate, benign iron compounds as vinegar or ammonia will. Sodium bicarbonate makes a buffer solution, which means if enough is disolved, it self-regulates its pH until too much is used up reacting with acids. It holds pH 8.4, which is according to the alkaline inhibitive solutions section of the linked article not basic enough to inhibit corossion if chloride ions are present. Since it's a buffer, a solution cant be made any more basic than 8.4, no matter how much is dissolved. Household ammonia is a stronger base.

Lastly, I would not use vinegar and table salt, which one may come across in some discussions of "de-oxidants" for copper etching. That actually makes some hydrochloric acid. Which is why the mixture is so great for cleaning copper. Remember that those etching fragile copper PC boards want a totally clean, oxide free surface for later fabrication and they may do some things especially for that reason. Any very thin oxides that form on a blade by stopping an etch will be removed by polishing or soldering preparation.
 
Thanks Ferguson. I'll try the lemon method first. I searched the back area at my work (electrical engineer) and we have gallons of ferrous chlorate. We haven't used it in years, because we machine our circuit boards mechanically (CNC). I don't think I'll try it on my knives. Seems a little much and ours being so old may be bad.

Thanks again,

Andy
 
That sounds prudent. You can also use warm vinegar. The lemon or vinegar just takes longer.

Steve
 
Interesting.

I use the cheapest, nastiest spray-on glass cleaner that I can find - Walmart sells this stuff for about $0.70. Make sure that it contains ammonia. This is some great stuff because it's inexpensive and useful - it neutralizes ferric chloride, neutralizes vinegar or citric acid, cleans and degreases prior to etching...and hell, you can even clean glass with it, so I'm told. ;)

Aproy, I swear by the chloride because I don't have the time for vinegar or fruit juice but they both work. If you do go with the ferric, be sure to cut it about 1/4 with water; it seems to improve the etch and it also makes the etchant far less dangerous.
 
Thanks for the tip, Dave. You sound like the daddy in Greek Wedding movie. Windex good for everything. How's life among the common man treating you?

Andy
 
Dave Rishar said:
Interesting.

I use the cheapest, nastiest spray-on glass cleaner that I can find - Walmart sells this stuff for about $0.70.
Click to expand...

Right you are Dave. I've just edited my "etching.doc" to reflect that.
Thanks,
Steve
 
aproy, The first two kukris I etched, I used vinegar. It worked pretty well, but it takes a long time. My FF especially, it took about an hour and a half to complete the etch. It was a good etch. I've since re-etched it with the FeCl method at Satori's, and while the FeCl didn't do "much" more, it did bring the hamon out a bit more, but it also shows the grain of the steel much better, and it also shows any transition zones that might be present. (and it's "A LOT" faster.

mike
 
aproy1101 said:
Wow! I definitely had the right impression. I can't believe it. How does the Indian Army use that thing? I wasn't planning to buy one anyway, too many HI knives on the agenda.
. . .

Andy
Click to expand...

I am not aware of any evidence that the Indian Army uses the models made for export to the West.
 
Thomas Linton said:
I am not aware of any evidence that the Indian Army uses the models made for export to the West.
Click to expand...

I may have misunderstood the 411 in this thread, my wife tells me this is quite common, but in the letter from Windlass didn't he say these are the same ones he has a contract to supply to the Indian forces? Maybe someone with a clearer idea of the situation could clear this up for both of us.

Andy
 
Windlass khuks are okay as gardening tools for hacking weeds and such, but Tramontina machetes are better suited to that sort of work, and are even more inexpensive.

Sarge
 
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