Bevel angel for Takobiki or yanagiba? 300 ish mm

Karburized

Karburized

Joined
Aug 30, 2012
Messages
104
A question,

Whats the typical bevel angle for a yanagiba and takobiki? I understand its a chisel ground blade, but I'm wondering what they typical bevel angle is.

My guess is 15 degrees or less depending on the thickness and length of the blade. This is for a 275-300 mm blade. I' imagine a 10 to 12 degree bevel would work well enough on 52100.

Thanks.
 
I never worry what the angle is...it is what it is. If you really want to know, just plug the numbers into a trig calculator. Lets say the blade is .125" thick and the grind is 1.25" high. That gives an apex angle of 5.73°. This will work for slicing fish, but is too shallow for vegies. So most of the time you put a tiny secondary on to stiffen the edge. About 10° is fine for that. 15° is a pretty large angle for a yanagi-ba. That would require a bevel of only 1/2".
 
please also take into account that the bevel on a yanagiba is not flat and will have an angle progression as you follow the hamaguriba nature of the blade road
 
For those scratching their heads over another puzzling Japanese word - Hamaguriba is the term for the continuous slight curve of the primary bevel.
It curves all the way to the edge, with no actual secondaries. This is often called a Moran grind, or the old Japanese term - Appleseed grind.

It is formed by making small flats as you sharpen/shape the bevel on the stones. Each flat is "blended" into the next one until the bevel looks like a smooth surface. When it meets the edge, it ends as a zero-grind. This technique was very important in shaping Japanese swords and knives made from the traditional billets with a hard edge and soft body. The steel sharpens very differently depending on the carbon content, and blending them together improved both ascetics and performance.

I find hamaguriba not a necessity in modern Japanese kitchen blades when using modern grinders and steels. The final edge seems to take care of itself when doing the final sharpening steps ( shiage-togi) by lifting the spine as you stroke the last few times on the edge. Some use a mouse pad backing on super-fine papers to get this effect.
Using a Rotary platen also creates a slight curvature of the bevel, quite similar to hamaguriba.
 
Thanks for the heads up folks!

well, this was a prototype for a non-traditional Takobiki out of .125" thick, 15n20. 1 1/8" at the point, widening to 1 1/4" at the heel. I don't have a radius platen so I just went ahead and made the grind with a flat back. The angle was 10 degrees and resulted in a grind line about 3/4" from the secondary bevel. Its basically a chisel. As of now, it's sharpened to 3 micron for test cutting using DMT stones. Works fantastically on dense protein like chicken, bacon, and lighter protein like tuna and does well pretty good on fibrous veggies. This will get cleaned up, a bolster and micarta scales will be attached and given to the sushi guy for a week or two of testing. Helluva bastard to grind even with a jig, all wobbly towards the handle. Took almost 2 hrs to grind this post HT'd blade for fear of cooking the edge.

1073111_10151763175544708_399052067_o.jpg


As an aside, here is a photo of my recent stuff. 7 1/2" chef, 6" nakiri and 4" paring. Wedding gift for a foodie friend of mine. 52100, stabilized Mallee burl scales, copper bolster and my mosaic pins. All it needs is a buff on the handle and bolster, some maker's marks, an edge and its ready to ship. The happy couple is on honeymoon right now, so these things are just sitting here.
1073305_10151757723619708_1920563560_o.jpg
 
Last edited:
Funny to see this come up, I'm sending a takobiki off for heat treatment now. Went with cpm154, .100" thickness and a 13 degree cut. I think I'll drop that down to a 10 degree when I do the finish hard milling. Also wonder about taking the thickness down to .090" or thinner but I will likely hold off on that for my next one. Might also switch over to s35vn for some comparison before I do a run of them.

I've also been chatting with a local sushi chef who will be giving feedback once it is together. Seems like a natural approach to development no? He wanted a tapered spine to shift the weight downward so it is a departure from the traditional look but the feel is pretty good so far. Think the balance point will end up about half an inch forward of the grip.

You may find that hard to sharpen without a hollow back. That isn't a decorative feature, it allows for just a pass or two on the flat side to be adequate for sharpening.

-Sandow
 
Yeah, the lack of a hollow was a primary concern, but it worked out pretty good without it. I just ran the stone down the back at about 1-5 degrees to the edge. So essentially its a chisel ground face with V grind edge. IIRC the secondary bevel was applied onto a .002 - .003 edge. No issues with it steering, going wayward or excess effort in keeping it straight in a draw-cut for the length of the blade.

.90" might be a good idea. .93" stock was the initial thickness i wanted start with, but i thought the steel would curl.

Working with sushi chefs in the U.S. is awesome. If you can develope some sort of casual relationship with them, I've found that can be a unique source of R&D data. Hell, the food hookups are great too. As particular as they can be, they just want a knife that easy to use and stays sharp. Also their process of food prep can be such brutal environment for steel and figuring out what works.
 
You can do the hollow grind back ( urasuki) on any contact wheel. Just angle the blade until the grind is as wide as the back. After making the hollow grind, and cleaning it up by hand sanding, lap the back dead flat and make the small flat at the spine and edge with sandpaper on a granite surface plate. You can't do the flat part of the back on a grinder...it has to be lapped or the edge will wander.

BTW, I find the tip looks best just angled back at 15-20° and left blunt. A small kissaki bevel is OK, but an actual sharp edge isn't of much use beyond accidentally cutting yourself.
 
I'm using a craftsman 2x42 right now and I'm not sure if the drive wheel is big enough for the stock i'm working with and plus i got a little bit lazy. I'll be sure to try it on my next one.
I though about grinding the point to make it look sword like, but i kind of wanted it to have a "kitchen tool" vibe instead of a "weapon" vibe.

Anyway, i just cleaned up the blade a little bit and I'm thinking of grinding the handle in a little bit more for clearance. I'll post up the finished piece later this week.
1074196_10151765222444708_103908421_o.jpg


Thanks again.
 
Your blade can easily be made as:
sakimaru-takohiki ( takobiki)...round tipped takohiki. The round tip looks very kitchen friendly.
or
kiritsukegata-takohiki ( takobiki) ....sword tipped takohiki. This is very similar to a kensaki-yanagiba....swird tipped willow leaf blade.
 
Last edited:
Sorry for the crappy pic.

Finished knife. Little bit of patina from test cutting. Sushi guy seems to like it a lot and wants a kirtsuke and usuba. Pretty stoked about it.
1085030_10151773962939708_369393240_o.jpg
 
Thanks, Stacy.


jklip:
No, unfortunately. Hence the "non-traditional" qualifier.
 
Last edited:
Very attractive piece!
Two questions: Stacy, when you mention a bevel angle, I'm assuming that it's always one side, measured from CL rather than including both sides? (doesn't apply to chisel grinds, of course)
Karburized, that's just a great looking handle- is that a shape that you worked out with the sushi shefs? What do they think of the handle feel?
Thanks,
Andy
 
elementfe said:
Very attractive piece!
Two questions: Stacy, when you mention a bevel angle, I'm assuming that it's always one side, measured from CL rather than including both sides? (doesn't apply to chisel grinds, of course)
Karburized, that's just a great looking handle- is that a shape that you worked out with the sushi shefs? What do they think of the handle feel?
Thanks,
Andy
Click to expand...


Thanks!
That's a standard handle I make with all my knives. The sushi chef really liked it as he test held a sample from a diferent knife. Its a little but shorter than a tradition Wa-style handle, but there is more mass and he is able to cut with better control with his normal grip.
 
You must log in or register to reply here.
Back
Top