Razor
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Post by Razor on Jul 25, 2022 1:25:38 GMT
Over the years in sword forums and sword groups there as been a lot of debates on edge sharpness. Things like a sword should be table knife sharp. Another common saying is that a razor sharp edge is to thin and will damage easy. and many other opinions on the matter.
From reading historical writings, European fight books, personally handling antiques, 31 years of martial arts(main reason I started was to learn how to use a sword), test cutting with swords since the late 90's, learning from sword researchers, and swordmakers come to the conclusion that swords were very sharp...Razor sharp. Specifically using the techniques that is described in the fightbooks, a sword needs to be extremely sharp.
Force is another factor to comes into play. The duller a edge is the more force is needed to cut and if a sword is to dull it won't cut at all. There is one guy that used to cut tatami with a sword that was so dull he would run his hand up and down the edge. The problem is, with the force and technique that was needed to do the cut would get himself killed if he did in a fight.
If we all ran around half naked, like an 80's barbarian B movie, then swords wouldn't have to be that sharp. The problem is we do wear clothing and a very sharp blade is needed to cut through them.
There is basically three levels of sharpness that I use to keep things simple.. They are paper sharp, newspaper sharp, and hair shaving/razor sharp.
Years ago at one of my sword gatherings/cutting parties, someone brought linen. So we wrapped five layers of linen around a Mugen Dachi tatami mats. There were swords there that had a three levels of sharpness. The Newspaper and razor sharp swords did very well. They both cut through the mats. The paper sharp sword didn't do so well compared to the sharper swords. It cut through the linen but only marked the mate. I always wanted to go back and do more testing on the difference level of sharpness.
I got a chance to and made this video. The target that I will use on this test is a gambeson over pork ribs tapped to a punching bag.
Enjoy 🙂
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pgandy
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Post by pgandy on Jul 25, 2022 14:07:07 GMT
A most informative video and thanks for sharing. You have shown better and with more detail what I have found. I have discovered clothing hampers the cutting ability. I bring my edges to shaving sharpness, but use 25° as standard. I have one machete that I reduced to 22½° as an experiment. That one cuts better and holds its edge and was planning on making that my norm and will do so now, and perhaps a bit more acute in time.
I feel remiss if I didn’t mention in real life that while one edge was desired and what was used were not necessarily the same. For example the British while desiring a blade that equaled a talwar’s edge went into combat with one much duller due to their steel scabbards. And a military edge that was put on was nowhere as nice the one you put on. In short, what was desired and actually used may not be the same.
As a result of your outstanding video I’ll make my edges more acute, as I had begun experimenting with, but needed a little push to make my norm. And as for combat, which I hope never to see, I’ve never imagined having a long, sword on sword, movie style session but see a short one measured in seconds regardless of ending, and using a shield in order to save my edge.
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Post by Lancelot Chan on Jul 25, 2022 15:47:07 GMT
A most informative video and thanks for sharing. You have shown better and with more detail what I have found. I have discovered clothing hampers the cutting ability. I bring my edges to shaving sharpness, but use 25° as standard. I have one machete that I reduced to 22½° as an experiment. That one cuts better and holds its edge and was planning on making that my norm and will do so now, and perhaps a bit more acute in time. I feel remiss if I didn’t mention in real life that while one edge was desired and what was used were not necessarily the same. For example the British while desiring a blade that equaled a talwar’s edge went into combat with one much duller due to their steel scabbards. And a military edge that was put on was nowhere as nice the one you put on. In short, what was desired and actually used may not be the same. As a result of your outstanding video I’ll make my edges more acute, as I had begun experimenting with, but needed a little push to make my norm. And as for combat, which I hope never to see, I’ve never imagined having a long, sword on sword, movie style session but see a short one measured in seconds regardless of ending, and using a shield in order to save my edge. 25 degree per side or total? :) |
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pgandy
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Post by pgandy on Jul 25, 2022 16:40:52 GMT
25 degree per side or total? :) 25°/side. This is what I use on my working tools and just carried over to my swords to lessen chances of damage. I’ve whacked through a pig’s leg on several occasions with no issues. But in view of the video and my experimentation with 22½° I think I’ll go that route. Just needed a little nudge. I can shave with the 25° edge so wasn’t in a hurry to change, just needed a nudge to get started. |
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Post by markus313 on Jul 25, 2022 18:04:10 GMT
Thank you, Razor. Great video, we need more of that stuff.
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Post by Lancelot Chan on Jul 26, 2022 7:48:14 GMT
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pgandy
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Post by pgandy on Jul 26, 2022 13:20:51 GMT
Thanks for sharing. I sharpened on the side of caution but it appears that I may have under estimated the strength. I have decided to decrease the angle across the board to 22½°. But will do so as they need sharpening rather than madly do so now. The only argument against this that I can think of is with a bowie of mine, my bundle of joy if you will. It lies on the table, shaving sharp, and with instructions to Hazel not to use. She didn’t for years then one day I noticed scratches on the blade. On examining it I noticed the tip bent and a chip. She had used it in the garden making ground strikes. She has no appreciation of blades whatsoever. I sharpen her kitchen knives about every other month. Those I’ll continue with the present grind. Tried 30° but went back to the 25. I remember years back she wanted a machete to cut grass. Being a Latina I assumed she knew something that I could learn so I observed. It was early morning and back light. WOW, the stuff that flew in the air was magnified by the lighting and I was indeed impressed. On her second cut I saw; she was hitting cement as well as grass and it was mostly flying cement that I saw. Fortunately, I had given her my loaner. That one will remain at 25° as the metal has a lower HRC.
And then I may be confusing a working knife with that of a sword and just used a 25° on everything for simplicity's sake. I have proven to myself that a 22½° will hold up on a machete of general use. Just hadn’t put in to general practice yet.
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Post by Lancelot Chan on Jul 26, 2022 14:22:38 GMT
It's a scary sight to see somebody hitting ground with sword. In our sparring it counts as weapon destruction and failure to the person who did that.
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Razor
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Post by Razor on Aug 14, 2022 6:48:12 GMT
25 degree per side or total? :) 25°/side. This is what I use on my working tools and just carried over to my swords to lessen chances of damage. I’ve whacked through a pig’s leg on several occasions with no issues. But in view of the video and my experimentation with 22½° I think I’ll go that route. Just needed a little nudge. I can shave with the 25° edge so wasn’t in a hurry to change, just needed a nudge to get started. I find when an angle is more than 22 the blade starts loosing it's cutting capacity. You can test different angles on the clothing worn in your area. If I remember correctly you live on an island or a hot climate? |
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pgandy
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Post by pgandy on Aug 14, 2022 19:52:46 GMT
I find when an angle is more than 22 the blade starts loosing it's cutting capacity. You can test different angles on the clothing worn in your area. If I remember correctly you live on an island or a hot climate? You are close, make that an isthmus at 10°N. I am in the process of decreasing my angles from 25 to 22½° but have not declared that a pressing matter and have only done so with machetes so far. My cutlass is not far away from being my first sword. Your post made me do further testing, something I’ve put off too long. The common dress here is one shirt. I wear two when off my property. I strongly suspect the bad guy(s) to wear a hooded sweat shirt over this. So I just completed new but not complete trials this morning. I used an old but seldom worn knitted shirt, so it still had much of its original sizing actually feeling a bit thick, of 100% cotton. I think mostly synthetic or partly synthetic shirts are worn here, but am not sure. From previous testing I know that knitted material is more difficult to cut than broadcloth as it tends to stretch and give. I am not willing to sacrifice a sweat shirt. I placed the T shirt over a gallon, water filled, heavy walled plastic jug. I used two blades, my Weapons Edge Klewang Cutlass and KHHI’s GI4 kukri. The cutlass has a 25° edge. I do not know what the GI4 is. It’s the factor edge that I honed. Both are newspaper sharp. Both cut through to the jugs, as expected. The kukri gave the largest, wound, also as I expected. With my antique 15” kukri I’ve done this using 3 rugs and made a larger wound channel. I don’t think the GI4 with its 15” blade will equal this. That 15” antique is my favourite combat knife but I rarely use it. I’ll do more testing time permitting. Afterwards and nothing really pressing as long as I had the cutlass out I decided to take the opportunity to change the grind. The job went faster than I thought but it is way too soon to pass judgement. No doubt it'll cut better, but the question is how robust will it be? I'll search around for some clothing and will continue. |
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