pgandy
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Post by pgandy on Dec 18, 2022 18:27:17 GMT
I did this with good results to my Windlass Regimental Kukri (Mk3) and may be of interest especially to kukri owners. First a minor description of my original blade. Many kukris including this one have a shallow recess running the length and about the width of the blade that could be called a hollow for the lack of anything better. The secondary bevel, called the patti, can butt up against this forming a slight ridge. This describes the make up of my and many newly made kukris. This ridge doesn’t appear on older kukris and has bothered me for some time as I imagined it having an adverse effect on cutting. One recent Saturday morning with no plan of the day I was setting at my desk fiddling with the Windlass and the sun was accenting the ridge more than normal. It’s also detectable by feel. So, with nothing better to do I took an 8” mill file to the ridge removing it. Then came the polishing process which I won’t bore anyone with, except on request. Below are both sides of the blade after finishing. Obviously, the next step was to test what I had done. The first test was newspaper cutting which it performed excellently. With that out of the way it was the back yard cutting test. I choose a 2½ L plastic bottle. Never before has this kukri made it through such a bottle leaving cuts of 3/ 4 through, but never halving the bottles. This time the upper half ended on the deck with the bottom remaining on the cutting stand, as has always been the case since. Something else also came to light. A phenomenon I’ve heard of but never witnessed. The knife is now holding its edge. Whoever attempted to put on the original edge, note I said “attempted”, had destroyed the hardening by getting the edge too hot. I had evidently cut through the soft metal and now have the good metal exposed. I just checked after several cutting sessions and it shaved, not as efficiently as when first sharpened but good enough.
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Deleted
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Post by Deleted on Dec 18, 2022 20:14:49 GMT
Awesome, I might try this with my kukri as well. If originals didn't have this ridge, I don't want it either. It doesn't seem to serve much of a purpose anyway
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pgandy
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Post by pgandy on Dec 18, 2022 21:42:24 GMT
Awesome, I might try this with my kukri as well. If originals didn't have this ridge, I don't want it either. It doesn't seem to serve much of a purpose anyway I am not saying that original kukris didn’t have the ridge that I’m finding on my newer kukris as there are so many variations some may exist some place. My antiques do not have such as edge, but they may not represent all kukris. Below is a kukri that I bought about 2 decades ago and it does not have that ridge.
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Post by Deleted on Dec 18, 2022 21:44:36 GMT
Awesome, I might try this with my kukri as well. If originals didn't have this ridge, I don't want it either. It doesn't seem to serve much of a purpose anyway I am not saying that original kukris didn’t have the ridge that I’m finding on my newer kukris as there are so many variations some may exist some place. My antiques do not have such as edge, but they may not represent all kukris. Below is a kukri that I bought about 2 decades ago and it does not have that ridge. Yea, fair enough. I want to remove the one on mine, regardless. Or at least shrink it a little
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pgandy
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Post by pgandy on Dec 18, 2022 23:28:23 GMT
My thought on the subject was that by thinning that section of the blade I would decrease the cutting resistance on the blade rather than make it look more like an older version and from what I’ve seen so far I’ve succeeded.
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Post by randomnobody on Dec 19, 2022 0:51:31 GMT
Interesting stuff, and food for thought on the pros/cons of secondary vs single bevels...
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Post by mrbadexample on Apr 15, 2023 19:26:44 GMT
I just did something similar with my Kailash historical service issue this morning. No major changes to the appearance, but it cuts much better now. Bringing back the primary bevel slightly and blending the whole thing to create a slightly convex edge made a big difference. Granted, the edge seems a bit less indestructible now, but I wasn’t planning on hacking up masonry blocks anyway. For the yard tasks I have, this kind of edge will reduce effort on my part. And, if anybody wearing textile armor decides to raid my quarter acre while I’m dealing with bamboo and vines, I feel much more confident that it wouldn’t get hung up on the clothing.
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pgandy
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Post by pgandy on Apr 15, 2023 21:37:54 GMT
I’m glad that your project worked out for you. I have every desire to do another, and I’ve narrowed it down to two kukris. At the moment there is too much is going on for me to attempt a new project.
Nearly every photo I can find of contemporary kukris appears to have more or less the same blade geometry which is not what I’m seeing in antiques nor what I see the Nepalese villagers using. I believe the makers of those sold on the Internet are made for westerners, which I can’t blame the manufacturers for. And as for the blade geometry, I’d say they are over built. And again, I can’t blame the manufacturers after seeing some of the abuses these knives are put through. The most appalling was watching a man totally ruining his kukri by repeatedly trying to cut a steel wood screw in half. At the end, out of disgust he threw his kukri in the river. I think that he was trying to cut the screw after watching it being done with an iron nail. The dummy didn’t know the difference between the two is the only thing I can think of. On my last kukri I thought that I was going to get what I was looking by specifying super sharp (which voided my warranty), but could tell no difference in the grind, measuring about 4mm at top of the patti as my others.
My antiques measure about 2mm at the patti and have held up for about a 100 years. I must say that their steel is softer which will allow the edge to bend as opposed to chipping. My new kukris are 57 HRC, a bit more than I prefer but so far no chipping. My favourite machete is 1.5mm at the sweet spot. And that one should have chipped by now but is holding up great.
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Post by eastman on Apr 16, 2023 15:06:13 GMT
If that is the video I am thinking of, he sells his own line of kukri. He tested the blade he sells in one video cutting a soft nail and tested his competitor's blade on a hardened screw.
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pgandy
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Post by pgandy on Apr 16, 2023 15:20:01 GMT
If that is the video I am thinking of, he sells his own line of kukri. He tested the blade he sells in one video cutting a soft nail and tested his competitor's blade on a hardened screw. Probably. The one I’m thinking of it was the company’s rep, iirc. Having said that, if his opinion of the knife he is representing, or the company he owns, is so bad that he throws it in the river, why air it? For those that don't know a steel wood screw is hardened with sharp threads to allow it to cut its way into the wood. A nail is usually made of iron and is soft. Some people have used small nails to demonstrate their superiority of their blades.
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Post by mrbadexample on Apr 16, 2023 17:19:07 GMT
I remember that there was a nail test that a lot of guys liked to do with their lockbabk Buck knives back in the 80’s. It always seemed odd to me. I mean, the wire cutters, files, and hack saws are all right there on the tool wall.
I just put the calipers on my blade. It’s right at 2.6mm now and very similar to my beefier antique. I have another that is under 2mm, but that is an older-style hanshee blade. Very light.
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Post by larason2 on Apr 17, 2023 4:46:20 GMT
I agree a convex edge profile has different mechanics than a concave one. I recently redid some of my chisels that I had previously sharpened on a grinder with stones, and they cut and shave so much better now. They felt sharp before, so it's not the sharpness per say, it seems to be how they interact with the surface of the wood. I think it's that the actual cutting edge is better supported/has better leverage, and you can roll the edge into a better position when carving. For cutting purposes, I've read a more convex edge cuts better at a range of cutting angles, so even if it's not perfectly aligned it can still cut well.
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