Yanagiba Fix and FS Polishing

[Altadan]

Hey all,

I've gotten a little polishing bug in me, and I though I may as well break down a nagura I got a while back for the purpose of making and playing with finger-stones.
I figured I'd experiment on my Young Samurai Yanagiba, which had a micro chip, and realized the dreaded moment is here - I gotta sharpen that thing out...
The previous time I put the Yanagi on the stones, I made one mistake and it took me HOURS to fix. Regardless, I did it, and now I have to do it again.

Just for fun, here's a photo of the yanagi with a quick-n'-dirty (and full of streaks) pass on a Takashima, after having a semi mirror polish on it. Obviously, more mud was needed to avoid those streaks, but, I only did that to see what sort of contrast it would give. I think there's potential. Later on I'll look into the new FS I made

With Takashima tomae contrast, streaks, and recklessness, over a mirror polish.

I'll update later when the issues are resolved, and I arrive at final polishing stages.
~
~
So, what am I here for?
Well, any help with the following issues is appreciated (feel free to reply with corresponding numbers)
(1) - Microchip: is there any quick way to get rid of a microchip?
I've the SG500 at my disposal, as well as the Atoma 140 (which I'm avoiding!). I've already put an hour+ and the chip has only shrunk a little. In the photo, the chip is marked by a small red spot. That area is touching the stone, but further up the blade there's a hollow spot... which leads to #2
(2) - Hollow spot / low grind Also, after all the work I previously did on this knife - there still remains a low-grind / hollow spot (see photo - blue short lines). should I be bothered by the hollow-spot if I'm planning to finger-stone polish this?
(3) - belly I've a tiny belly/high-point on the edge close to the heel (see photo - golden line, though its too small to see). It doesn't bother me too much, but, you who are experienced - how would you deal with that? A quick way, I suppose, would be to lay the edge directly on the stone the other way I can think of, is either to spend more time/passes on that area, or applying more pressure there.
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Click photo to enlarge

with SG500 finish

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Thanks!
Dan

[ken123]

If you spent an hour on a 500 stone you need something coarser.The 140 may do the trick but it will leave deep scratches.

Your hollow grind also needs to be ground out. This will initially need a coarse stone. Subsequent stones will work best if they are soft (1200 Nubatama or Aoto or Monzen) as these will level out the surface irregularities. As mentioned earlier you are not ready to use the Takashima or naguras. Too big of a jump. Many naguras will be too coarse - coarser than your takashima, so you will be going backwards. Fingerstone preparation is also largely a waste if time. I can talk about this later

---
Ken

[Altadan]

-=-=-Part 1-=-=-

Well,

In the meanwhile, I went ahead and remove the microchip. Took me a good 2-3 hours on the SG500.
It turned out quite well, and sharp, but... I ended up over-grinding the front half, or should I say, under-grinding the back half of the knife, towards the heel. That belly I mentioned/showed in the previous photo is now more pronounced
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SG500 with over-ground front

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In any case, I decided to move up the grits I have available.
I skipped my generic little 1k, and hopped over to the to an SP2k. The finish was at once both peculiarly shiny at the core and less uniform and streaky on the cladding.
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Shapton Pro 2k

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Then I had no choice but my generic little 6k. It's a "Sharp Pebble" I got off Amazon when I first first started. It's smaller than the full-sized stones sold on CKTG, but the 1k works, and the 6k is a real pleasure to use (people's descriptions of the Rika 5k always resonated with my experience on this one). Having said all that, the finish it leaves is hardly nice looking on a single-bevel (possibly not a true 6k);
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6k finish

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Finally, I moved back up and over to a small Takashima Tomae, which is a rather muddy and soft stone. I was hoping for nice results, and they weren't too bad, but I think it had trouble removing the 6k's scratch (or streak?) pattern. Plus, I think by then I was losing patience, as the movie my wife+friend were watching ahead of me was coming to an end, and the night was not as young anymore...
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Takashima Tomae with streaks

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[Altadan]

-=-=part 2=-=-

I thought that's all I had, and I told my wife before going to bed that for the time being, I think I just don't have what it takes to create one of these nicer kasumi finishes, whether dark, or milky, or at least smooth.
A trick I learned from Steve is using diamond paste on a hard-felt cube. But in this case, with the streaks being what they are, removing them with diamond paste would be too laborious, and it would remove whatever finish the Takashima left, and replace with something closer to a mirror.

But, as a last push before bedtime, I decided to give a go to a finger-stone I made last week form a hard nagura stone I bought a while back for the purpose.
Generally speaking, hard-stones are hardly the best suited for the job (excuse the pun), but I figured that with added mud should help (I kept it from the grinding/production process when I made these little buggers).
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Fingerstone at the bottom, with the mud in the red-cup.

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It was really fun trying out something new.
I dabbed mud on the knife several times throughout, and the little bit of stone produced on it's own, too. Extra drops of water along the process helped keep things moving, and then, at the end - I got myself what I wanted, more or less.
A smooth, milky, contrast. Voila:
~

~
Would have been nice to have a dark finish, and it would have been nicer had I not over-ground the front have of the blade.
But, all in all, I came out with a sharp yanagi, and a rather nice finish, and that's an achievement (of what value I am not sure).

I realize, of course, there are other - and better - ways of doing all this. Please feel free to contribute!
Hope this thread helps someone along the way.

[Jeff B]

Looks great Dan, you should give yourself more credit!

[J david]

That's a lot of work with a rewarding finish. Congratulations.

So long as you've done the work ahead of time, an acceptable streak free finish can be had with a quality natural (or synthetic) bench stone. It comes down to pressure control, stroke control, and patience. I will give you a tip for what I call a "cheat" kasumi finish when you don't have the time or you don't want to use fingerstones.
First, lay down a polish with your desired stone as clean and consistent as you can. Next, collect some mud from the stone on a fingerstone sized piece of 2400 micro mesh and give it a treatment. It will even out the kasumi and eliminate the streaks. It takes a close inspection to tell the difference and takes half the time.

[Altadan]

Thanks for the kind words, Jeff and J david.

If I hadn't already had that piece of hard nagura, I would have liked to try the much softer hakka that Ken has in stock. A small muddy piece might have gone a long way in this endeavor, and would have likely saved me time. FS take a while to make
Maybe Ken can say a word about these

J david, I may well try that trick too

[pd7077]

Nice work Dan! David gave you some good advice there. Getting a good feel of pressure and stroke control takes a bit of practice, but it’s definitely crucial when trying to get a streak-free polish. I practiced on a kiridashi before going full bore on a yanagiba, and it really helped a lot.

[Altadan]

Nice work Dan! David gave you some good advice there. Getting a good feel of pressure and stroke control takes a bit of practice, but it’s definitely crucial when trying to get a streak-free polish. I practiced on a kiridashi before going full bore on a yanagiba, and it really helped a lot.

Thank you very much, Steve. Chatting with you about the finger stones gave me a whole lot more courage to go ahead
When I first applied the FS I was immediately cognizant of the pressure, and the need for more mud. But once the mud was on I was tempted into applying more pressure, as if that would achieve the desired result faster... that is, of course, the opposite of the truth. Finesse and light pressure are key, I see that more and more.

I looked for kiridashi's to practice on too, after that recent close-up shot you posted somewhere. But, without having found one with a nice wavy clad-line like yours I just knew my practice lies elsewhere I nabbed a half-priced Yushimitsu Fugen W#1 which I intend to use for that purpose.
Besides, Its price notwithstanding the Young Samurai is a great piece of workmanship (at least mine is). At the same time, with its price tag it is also not too far out of reach to replace, should a need ever arise.

[ChefKnivesToGo]

-=-=part 2=-=-

I thought that's all I had, and I told my wife before going to bed that for the time being, I think I just don't have what it takes to create one of these nicer kasumi finishes, whether dark, or milky, or at least smooth.
A trick I learned from Steve is using diamond paste on a hard-felt cube. But in this case, with the streaks being what they are, removing them with diamond paste would be too laborious, and it would remove whatever finish the Takashima left, and replace with something closer to a mirror.

But, as a last push before bedtime, I decided to give a go to a finger-stone I made last week form a hard nagura stone I bought a while back for the purpose.
Generally speaking, hard-stones are hardly the best suited for the job (excuse the pun), but I figured that with added mud should help (I kept it from the grinding/production process when I made these little buggers).
~
Final Pre FS.JPG
~
It was really fun trying out something new.
I dabbed mud on the knife several times throughout, and the little bit of stone produced on it's own, too. Extra drops of water along the process helped keep things moving, and then, at the end - I got myself what I wanted, more or less.
A smooth, milky, contrast. Voila:
~
Final - Post FS.JPG
~
Would have been nice to have a dark finish, and it would have been nicer had I not over-ground the front have of the blade.
But, all in all, I came out with a sharp yanagi, and a rather nice finish, and that's an achievement (of what value I am not sure).

I realize, of course, there are other - and better - ways of doing all this. Please feel free to contribute!
Hope this thread helps someone along the way.

Looks great Dan.

[Bensbites]

Looks great!

[Altadan]

Thank you kindly.
I realize I've gotten lazy with using my phone instead of my DSLR... I suppose the photos do give the general idea, though.
Maybe later I'll post a more recent one, with the cool purple/gold patina that's going on after the recent sushi batch

[arthurfowler]

Well done Dan. A great thread to read. I know that as I slow down on buying knives and I sharpen them all, the polishing element will become the new hobby by either restoring, improving or trying new finishes.

My concern is that you have far more patience than me!!!

[Altadan]

Here we go,

these are sharper photos I took back then, after the first batch of sushi prep
disclosure: wife was carrying, and the fish had to be cooked, which ain't quite the norm, but turned out decent nonetheless.