Flat to Convex and Final Rough Sharpening on 400-800 Grit - part 2

Flat to Convex and Final Rough Sharpening on 400-800 Grit - part 2 | ハマグリ刃の研ぎ方

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Күн бұрын

Part 1
• Key Points To Start Ro...
Part 3
• On the way to a kasumi...
Many of you may want to know about Convex, also known as Hamaguri or Clam Shape.
Generally, the convex edge is shaped entirely edge roundly, from Kurouchi line but this time we are sharpening it Flat To Convex which means the blade road is flat and rounded only the edge.
Why do we use that method and how is it done? Why does it need the flat on the blade road?
The technics and eyes; Ivan learned from Sakai Japan, we hope you will deepen your sharpening knowledge more through the video.
包丁研ぎ歴25年、現在は日本三代包丁産地である大阪府堺市で包丁会社に勤めているカナダ人です。
日本でハマグリ刃と呼ばれるコンベックスの研ぎをしました。鍛治師である真崎氏の素晴らしい包丁の形を残すため、今回は刃先だけハマグリ刃の仕上を採用しています。
今回の研ぎでは、眞崎直樹氏の黒打牛刀を使わせていただきました。貴重な包丁を研がせていただく機会をいただいた、包丁コレクターの友人には感謝しております。
[ Previous Recommended Videos ]
🌟Who is Ivan?
• My 25 Years of Hand Sh...
🌟My Sharpening Work - Kurouchi Gyuto Sharpening from Blacksmith until Natural Stone Sharpening by Ivan
• Natural Stone Polishin...
🌟My Sharpening Stone - NSK Kogyo Diamond Stone
• An Introduction to NSK...
🏠NSK Kogyo Diamond Sharpening Stone - Komon
komonjapan.com/collections/ns...
Hello, we, Ivan and Yuka have a unique experience of Japan through our business and life such as rich Japanese culture, exquisite crafts, breathtaking natural landscapes, beautiful foods and exciting travel, we share what we feel through our business and our lives. By sharing such our experiences, we hope that you will enjoy through our videos!
00:00 - 400 - 800 Grit, and Convex Sharpening
00:40 - What is Convex Edge?
01:27 - Sharpener Morihiro's Technic on Hamaguri Edge
01:47 - Two Key Point for Checking Convex Edge
02:52 - Konosuke and Morihiro
04:49 - Tamahagane Gyuto by Swordsmith
05:39 - Chose Flat to Convex on Mazaki's Gyuto
06:49 - Class - Convex is Fully Clam Shape
07:34 - Class - Why Chose Flat to Convex
10:02 - Class - Flat to Convex on 200 Grit
10:35 - Class - Flat to Convex on 400 Grit
11:27 - Class - Flat to Convex on 800 Grit
13:16 - Changing the Scrach Pattern on Each Grit
15:37 - Sharpening on 400 Grit
17:00 - Check the Angle on Degital Protacter
17:59 - Learned from Morihiro
19:10 - Check Point Before Moving onto the 800 Grit
21:03 - Poit Sharpening on 800 Grit
21:53 - Class - Flat to Convex on 800 Grit
22:58 - Sharpening on 800 Grit
24:31 - What to Check Before Moving onto the next Stone

Пікірлер: 22

@kevintran3158 Ай бұрын

Love that your explanations are getting more clear and we progress videos.

@Yupppi Ай бұрын

Really really fascinating when you go in-depth on the whole thought process of how you decide on the way to approach and execute the plan. I believe it really helps people who try to become better at sharpening, to move from having technique to having a good strategy. And what I find particularly helpful is that you don't show just different geometries and why something is good, but the context and how to go about with an existing item and geometry. Like how to actually make what you want for a result. People often warn you about not doing a straight push/pull on the whetstone to avoid rounding the edge and killing the sharpness. Which is why in my head convex geometry seems extra difficult to sharpen. However this method seems approachable. I have already tried (with Ivan's and Murray Carter's techniques) with a cheap kitchen knife to straighten it out and create two distinct bevels and thinning out the knife and it really helped in understanding the process and performance, to be able to actually see what your work is doing and to get the basis for sharpening, the pre-sharpening process, in a better place. The scratch direction change is also really helpful for observing the effects. Now I've maintained a better and smoother cutting performance than I've ever had for a good while, so I'm very happy with the lessons. Btw NSK seems to be picking up recognition here in the west as well as your videos with their stones are getting published. My go to sharpening tools entrepreneur just added a category for upcoming NSK products in his catalogue. And he tends to have a pretty long trial period before he decides on a new brand and which products to introduce in his small shop, so seems like NSK has made an impression.

@ivanyuka-japan Ай бұрын

Thanks so much for the great insight into my work, I often try to approach sharpening in two ways primarily what the blacksmith intended and how or who will be using the knife. From here I go onto piecing together a plan of approach.

@LtKwasretaken Ай бұрын

Thank you for going so in-depth. Very informative and helpful, and well presented.

@lunfardo Ай бұрын

Great video anyone curious about polishing should watch. Would be great if at some point you could walk through how exactly you ensure a uniform polish across the curved surface

@ivanyuka-japan Ай бұрын

Thanks, we will include this in the next few videos

@thiago.assumpcao Ай бұрын

Food adhesion happens because of capillary adhesion effect, less surface contact area means less sticking. The overall geometry for Japanese knives take this into account and even their Flat Grind already offers protection because of the shinogi line. Their design is so much better than a western Full Flat Grind. S Grind, hammered finish and irregular surface from the kurouchi also helps avoid food sticking.

@scharfermax Ай бұрын

Another invaluable demonstration of the art of sharpening! Thank you, Ivan, for these clear and well-illustrated explanations! It seems to me that the information at 18" is particularly important, but personally, I didn't understand the connection between the 200 and 400 scratches... Perhaps there will be additional information in the following parts?? Also, the question of the pressure to exert during the different stages of making the hamaguri: Would it be possible to have an idea of what pressure is being referred to, and if it's measurable or just based on feeling? Is a strategy with a marker drawing a solution for working precisely when one doesn't yet have the required experience? Thanks again and nice hommage to Morihiro!

@ivanyuka-japan Ай бұрын

Thanks I’ll go into more detail about this in the next video

@scharfermax Ай бұрын

Thanks, Ivan! Looking for to learning more about it!

@TheMegalegenden Ай бұрын

This type of content is wonderful ❤ more of this :)

@yaniv5055 Ай бұрын

Thx for this great video Ivan super informative 🖤🔪🎶🍻🎶

@sanduliaka Ай бұрын

Thank you!

@AKBoost Ай бұрын

Nice work!

@revilolavinruf Ай бұрын

Great vid!

@jjshane72 Ай бұрын

can you guys can maybe invest in a clip-on-mic to improve audio quality? I really enjoy watching and listening to your videos while I work or do other things but sometimes Ivan's voice is a bit too quiet

@ivanyuka-japan Ай бұрын

Thank you for watching while you work! Sound has always been an issue for us as well, and while it's much better now that we have a Sony external mic, we'll look into getting a clip mic as well.

@jjshane72 Ай бұрын

@@ivanyuka-japanI enjoy watching your videos as I work on my own knives and try/practice different techniques, your videos has helped me a lot but since I like to work without headphones on so sometimes your voice gets a bit quiet 😅

@jjshane72 Ай бұрын

@@ivanyuka-japanalso I've heard that a good way to blend the 2 bevels is with a rocking motion and soft stones at the point where the 2 bevels meet, is this a good way to do the blending?