musings of a deranged polisher

Shop Knives and stones on ebay
Kitchen Knife Forums

Help Support Kitchen Knife Forums:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
My unshu yukimitsu sr takohiki has crazy convexing at the heel, similar to what you're talking about but a bit different lol.

Normally for slicers, most of which are sharpened in Sakai, I have to lift up at the heel to hit the blade road there while sharpening. But the grind and blade road thickens dramatically there. . . Very confusing lol, to handle the shinogi there. So I have to sharpen it less if I want to mantain shinogi height, or to avoid reprofiling
 
refcast said:
My unshu yukimitsu sr takohiki has crazy convexing at the heel, similar to what you're talking about but a bit different lol.

Normally for slicers, most of which are sharpened in Sakai, I have to lift up at the heel to hit the blade road there while sharpening. But the grind and blade road thickens dramatically there. . . Very confusing lol, to handle the shinogi there. So I have to sharpen it less if I want to mantain shinogi height, or to avoid reprofiling
Click to expand...
Shigefusa yanagiba are particularly tricky to manage in this regard if you want to avoid a climbing shinogi at the heel. Basically anything with a decent amount of rapid taper above the heel really. I see it on some heavy taper semi integral wide bevel western smith knives too - you see that shinogi rise at the very heel dramatically.
 
ethompson said:
Been a few weeks since I've had any energy for this type of sharpening work, so just circling back to this one.

After some further work, it's pretty clear to me that this blade was ground with a little warp in place. While the edge and spine were dead straight and the bevels fairly even when I unboxed it, the more I worked the bevels the more unevenness became apparent. Nothing crazy, but something I would've caught earlier if I'd spent a bit of time with a straight edge examining the hira and shinogi before starting rather than just eye balling it.

The pitting at the edge, particularly at the heel, was also worse than I gave it credit for, I had to shave through a decent bit of material to get to something stable.

Then there was the grind, which is deceptively complex. Looking at the choil, you'd be forgiven for assuming this is actually an axe, not a nakiri. But at the "tip" its rather thin and lasery. So dramatic is the distal taper, the overall grind angle at the tip is more than twice as acute than at the very heel. The majority of that change occurs in the first 60mm of the knife as the grind rapidly thins out. That's a lot of transition to manage in a very short length of blade. I've "finished" at 400 grit only to find I wasn't happy with the shape of that transition at 1500 grit twice now. Here I am again halfway between 200 and 400 grit...
View attachment 302505
Shaping can be tedious, frustrating work. And it involves synthetics, which are never as fun as naturals. But the more I do it, the more I start to understand it, and the better I get at it the more I relish it. This is the foundation work that not only makes the natural stone polishing easy and enjoyable, but also leads to some really excellently performing knives.
Click to expand...
This is why that hollow ground hira right biased magnacut one i did in the last batch was so difficult, that and it being a kiritsuke with a flatter profile made it harder.

I made it with a dramatic taper at first and also having such a right bias made the left side difficult to get right, and just in general. It was a wild knife.
 

Fingers are bleeding so stopping for today. Further stone work would be cosmetic only, this one is ready to go.

Steel is hard and very glassy. I think it’s some type of shirogami or other very simple carbon. But hard. Takes a great edge, but not in a hurry.
 
New project. Been on my “bench” for well over a year. Finally getting to it. 360mm honyaki yanagiba. A TON of work needed on this one. I expect it’ll be late June before I get it fully wrapped up.

@refcast, happen to remember who the smith family was on this one? Sakai Umesaku brand, the ones with the crazy nice high layer Damascus stuff a few years back.
 
ethompson said:
Haven’t had much time, if any, to do much sharpening recently, but I have a little breathing room this weekend, a smallish knife I want to work with, and some stones I want to test.

Start:
View attachment 310160
Click to expand...
I remember putting my BB on stones and realizing just how thin it was behind the edge.

Did you have any problems setting the geometry due to this?
 
NickMinton said:
I remember putting my BB on stones and realizing just how thin it was behind the edge.

Did you have any problems setting the geometry due to this?
Click to expand...
Yes, working with thin knives is more challenging than thick knives - the angle at the shinogi is shallower, you have to be massively diligent about not abrading the edge too much, the knife is more prone to moving around (bending, warping, etc), and so on. I cut in a fair size bevel at maybe 60° per side on a 800 grit stone and then stropped at nearly 90 leaving a slightly thickened very dull edge before starting. Need to check the edge thickness and your abrasion constantly and try not to use the edge as an angle guide along the spine. So yeah, keeping things crisp and true to the makers intention is a bit challenging.
 
ethompson said:
Yes, working with thin knives is more challenging than thick knives - the angle at the shinogi is shallower, you have to be massively diligent about not abrading the edge too much, the knife is more prone to moving around (bending, warping, etc), and so on. I cut in a fair size bevel at maybe 60° per side on a 800 grit stone and then stropped at nearly 90 leaving a slightly thickened very dull edge before starting. Need to check the edge thickness and your abrasion constantly and try not to use the edge as an angle guide along the spine. So yeah, keeping things crisp and true to the makers intention is a bit challenging.
Click to expand...
I haven’t worked up the courage to lay my BB bevels down yet. Someday…maybe
 
I undertook a similar project with one of my BBs a few weeks ago. For me, the challenge was mainly related to the slightly concave grind that, according to BB himself, eventually fades over time and sharpenings/polishing sessions, resulting in a higher shinogi line and a more convex grind. Of course, the downside is - for me at least - the loss of a few millimeters in blade height. Nevertheless, I'm quite satisfied with the result for this gyuto with an excellent quality/price/performance ratio and hope to acquire another one soon.

 
I’m hopping to lose only a few 10ths of a mm with this, which is seeming very doable. Shinogi will raise slightly of course, but that’s okay by me and preferable to loosing edge height
 
ethompson said:
I’m hopping to lose only a few 10ths of a mm with this, which is seeming very doable. Shinogi will raise slightly of course, but that’s okay by me and preferable to loosing edge height
Click to expand...
It's undoubtedly possible for you, but sadly my technique didn't allow me to save those few millimeters. The challenge was even more delicate since the BBs are characterized by this very low grind, which makes finger placement even more tricky, because with the slightest wrong movement or excessive pressure, an overgrind of the shinogi and scratches left on the superb cladding (unfortunately, I experienced this) will quickly occur. Anyway, I'm eager to see what you'll be able to achieve with your expertise and patience!
 
What is a bb?

Also every time i load this.page the ammount of videos on it makes my browser want to crash. 😂
 
Work mostly got in the way this weekend. Also never forget that really good geometry work is hard. Made a few stumbles late last night and again this morning and feeling a little down
 
ethompson said:
Made a few stumbles late last night and again this morning and feeling a little down
Click to expand...
I’m very grateful for the advice I read here (possibly even from you!) that the best approach to growing frustrated or dejected is to put it away and come back to it another time.

For some projects that was for weeks 🥲
 
As happens when I’m struggling to execute on my vision for a given project, I tend to switch gears for awhile. I always have 3+ things going at once seemingly, so this is usually easy.

One of the things I’ll be working on with the honyaki yanagi I mentioned awhile back is getting the shinogi reshaped along the length of the blade. This will require managing the distal taper by adding some twist to the hira and adjusting the angle of the kireha. Doing a small scale study of that here with a small project knife.
IMG_9655.jpeg

This low stakes, no expectations distraction has been a really enjoyable way to unwind the day.
 
You must log in or register to reply here.

Latest posts

Back
Top