Sharpening to Kaisei on a Tamahagane Honyaki Knife + HRC Hardness Test

[@Yupppi]

Fun and timely video to me. This fall I had material labs about steel hardening (the test was about cooling time and created roughly HRC from 55 to 30 for Imatra MoC 410 M steel). Taught me a lot about how important the even and quick cooling is to the hardening process. There was also labs about aluminium and steel hardness as well as microstructure like carbon deposits in martensite/austenite in (grey and ductile) cast iron for mechanical engineering studies, very curious. The uni had got a new type of hardness tester we got to try as well, really fascinating when you actually get to view a microscopic image of the hole on the monitor and defining the result by measuring the hole via computer software. Japanese katanas and tamahagane were also mentioned. To test blades, if it was a regular thing, it would probably be reasonable to build some sort of jig that holds and supports it parallel to the diamond. I wonder if anyone has bothered with that. I've been so busy I haven't been able to keep up with the video series, but I really enjoy watching these on Christmas vacation, the commentary has just improved. Learning so much of this unique expertise. Why aren't the tang straight corners rounded? I'm used to the idea that wherever there are straight inside corners, you round them, just like behind the blade. Is the focused structural stress just not relevant in cases like kitchen knives? Admittedly they're not load bearing in the same sense or measure as mechanical machines and power transmitting parts. And talking about the hardness's difference to sharpening, when I started learning sharpening, this titanium blade made me scratch my head when it felt like I did nothing to it. Unsurprisingly having a bit of material studies and curiosity revealed a lot about it to me. Like how if you use titanium over steel, you probably want to 3D print it preferrably instead of machining (or sharpening) it.

[@maxjansen8110]

Would love to see more knives of different manufacturers HRC tested. The video was very nice to watch!

[@keithjohn1650]

this has to be one of my favorite series, it's like a insta click whenever i see your guys' videos, please keep them coming!

[@ivanyuka-japan]

Thank you for your support!

[@SC-wi9md]

That sujihiki just keeps getting better and better. Nice Weber workshops Bird too. Really don't see many of them!

[@ivanyuka-japan]

The Bird is absolutely amazing! Our friend gave it to us for Ivan’s birthday, and we’re so lucky to have it.

[@nafis6668]

Harder knives are easier to deburr cleanly , leading to higher sharpness. With softer knives , the burr tend to flip flop a lot before releasing, leaving less acute edge.

[@odonvasc]

Can't wait to see this piece of art finished! Amazing!

[@Nebulax123]

Really enjoying this one. My daily carry knife is Tamahagane and I really love it. I think it would RC around 58 but is has really good edge holding. The other knife that I carry the mose is Blue Super around 65 RC and does take longer to finish out.

[@ivanyuka-japan]

It sounds like you’ve got a great daily carry selection! Both steels have their strengths, and it’s great that you’ve found what works best for you.

[@WormyLeWorm]

Ok, I have to ask, what french press is that?

[@davids2588]

"The Bird" from Weber Workshop

[@WormyLeWorm]

@@davids2588 Thanks

[@ivanyuka-japan]

The Bird is between a French press and a drip, and its design and ease of use, not to mention its taste, are excellent!

[@martins.5977]

Verry interesting. Do you polish those little holes from the test out later?

[@ivanyuka-japan]

Yes that’s correct during rough sharpening the small holes will come out

[@martins.5977]

Ok, got it. I thought you were though rough sharpening with these blades.

[@sharamkh]

Interesting! But now I really want that coffee kit 😅 Do you want to share the name?

[@ivanyuka-japan]

The French press is called Weber Workshop, “The Bird”

[@AKBoostBBQ]

Awesome!

[@laforgeduronin1597]

Interesting 🙂

[@rockchopknifeco]

Great insight but I was staring at the cheesecake 😍😋so lost concentration for the last few minutes!

[@Hi-FiChess]

lol

[@ivanyuka-japan]

Haha, I bet it was a great treat after the shoot! Now we can enjoy the spice latte too!

[@manuelbousquet]

❤

[@T_chanell]

Pisau asli jepang memiliki HRC yang tinggi 60+ ❤❤, sulit rasanya membuat HRC yang tinggi, proses hardening sering membuat pisau pecah bahkan rapuh. hanya orang-orang yang ahli yang tahu rahasianya.

[@ivanyuka-japan]

Making knives with high HRC requires skill, but I’ve learned from many blades that it's not the only measure of quality.

[@La_sombra_de_la_luz]

Hay durómetros modernos que miden la dureza del acero por ultrasonidos sin dejar marcas: kzbin.info/www/bejne/nGqvdXRpo5h3ibssi=__bwLty8oeEC3Pa9 kzbin.info/www/bejne/e3eqpJV_ZZl5g6csi=KMdO_qSd5prFCWZ6

[@ivanyuka-japan]

Thank you for sharing the video!

[@radoslawjocz2976]

This woman is beautiful. I guess she is your wife.

[@ivanyuka-japan]

Yes she is I’m very lucky !