Remove KU and refinish with cloudy finish?

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Yeah, much better than what I expected based on how the KU looked. Do you think it means the KU might have been chemically applied and not leftover scale from the forging process?
 
Amazing how doing that kind of work gives you a sense of ownership. You no longer fear really messing it up.

CiderBear said:
Yeah, much better than what I expected based on how the KU looked. Do you think it means the KU might have been chemically applied and not leftover scale from the forging process?
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Not an expert; but chemical KU's are definitely a thing.
 
I polished some horn ferules using a drill, a cotton buffing wheel, and white jewelers rouge, they came out very nicely. Got the wheel and rouge at Ace Hardware.
 
Ah, that came out nice! Thanks for sharing.

I've been thinking about doing the same to my Moritaka Nakiri. What stopped me so far is the fact that it is ironclad and the cladding is much more uneven than your knife.
 
Thank you @miggus @Midsummer and @SilverSwarfer
Yeah it actually came out a lot better than expected. There was a low spot in the blade road near the heel that I only noticed when I tried to make it look kasumi-ish. Grinding that out with a 1000 grit stone (I only have a Gesshin 1000/6000) was... not fun. I'm actually impressed how dark i can the blade road to look with the 1000 side of the G1/6k though. Makes me want to try Jon's Jinzo Aoto so much more.

Any advice on what I should do with the blade face? It looks pretty matte atm, I'd like it to be a bit shinier, I think. I'm thinking sandpaper, but I'm not sure which grid to get.

@dafox thanks. It sounds like I need some sort of tools for the horn, then. I bought this kit Dremel 684-01 20-Piece Clean & Polish Rotary Tool Accessory Kit With Case https://www.amazon.com/dp/B00005LEXV/ref=cm_sw_r_cp_apa_i_.bJIDbPSNFZ57 thinking that I could use it outright, but no, I need a Dremel tool to attach it to. Damnit :(
 
I’ve had some easy success with 0000 steel wool and Autosol or Simichrome if you’re aiming for shiny. Autosol “original” formula has some abrasive you can feel during polishing while Simichrome seems finer. I’d recommend getting both, especially if you like the shiny things (like me: I’m not a patina guy)! Aside: you don’t really need the steel wool, i just have an easier time of i develop any pesky rust spots.
 
Removing KU works well with citric acid dissolved in hot water, the stuff used for cleaning coffee machines...

.. learned that by mistake, added some in coffee mixture for a forced patina, and the KU was history :D

Regards

Uwe
 
DDC68C17-A3D3-4B10-A03F-8751A178498A.jpeg


Used to look like this:

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Haven’t finished with the polishing, obviously, but removing the KU wasn’t a big deal. Took at most 30 min with 220 grit sandpaper, and the grind underneath was just fine. Cleaning up the scratches takes a while, of course. Given that the cladding is stainless, what’s the point in giving it such an awful looking KU finish? It looked even worse in person.
 
@ian does it mean that Watanabe's KU finish is chemically applied afterwards, and not a byproduct of the forging process?
 
CiderBear said:
@ian does it mean that Watanabe's KU finish is chemically applied afterwards, and not a byproduct of the forging process?
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Yea, I’m assuming so, but I don’t know. It sure looks different than other KU and I’ve heard people talk about him using a ‘blueing agent’ or something. Seems unlikely that the grind would be so good if it was real, but what do I know. In contrast. I’m doing another KU removal on a knife I bought for $30 on BST, and this is requiring basically a complete regrind of the knife....

Btw, on the Wat above I couldn’t use stones on most of it due to concavities in the grind. On both Wat’s I’ve owned, the blade road on the back of the knife has been slightly concave, and on this one there’s a shinogi “ridge”, ie the front face of the knife above the shinogi line is also slightly concave.
 
Yea, it is wobbly for sure. You can see the same wobbles with the KU, but it might be more noticeable without. Doesn't bother me much, though. The Mizuno I have also has a kind of wobbly shinogi, but they must tape off part of it when they finish it, because OOTB the (differently finished) blade road makes it look like the shinogi is impossibly perfect.

Anyway, if it ends up bothering me I'll refinish it in a way that you can't really see the shinogi.

I'm kind of confused by wobbly shinogi lines, though. Presumably, these knives are ground all over (the Miz at least), so how do you get a wobbly line?
 
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You can do this by hand. Just use fine grit sand paper, and micro mesh pads if you have them
 
Here’s the most recent polish on the formerly KU Wat.
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I straightened out the shinogi line (more or less) and gave it a bit more distal taper, while flattening the part above the shinogi. There are still some concavities above the shinogi, and the geometry is irregular above the shinogi near the handle. However, I like how it’s real thick near the handle, and I imagine the slight concavities will contribute somewhat to food release, so I didn’t mess with them as long as they were far enough above the shinogi. Also rounded the spine and choil. This is also my first real kasumi. Not perfect, but ok!

Anyway, it looks incomparably better than when it had the awful kurouchi.

Edit: also, this was my 1000th post! :)
 
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Does anyone know if there's a suitable dremel attachment that can remove small spots of kurouchi that lay inside indentations? I've sanded most of the kuro off a couple of knives but each have a few remaining deeper spots that I'd like to remove. Not looking for an even metal finish and honestly don't mind if there are still a few spots left, just not a fan of rough kuro finishes.

I was thinking something that isn't extremely abrasive, maybe a wire brush attachment? Or any other ways to do it short of FeCl3?
 
4wa1l said:
Does anyone know if there's a suitable dremel attachment that can remove small spots of kurouchi that lay inside indentations? I've sanded most of the kuro off a couple of knives but each have a few remaining deeper spots that I'd like to remove. Not looking for an even metal finish and honestly don't mind if there are still a few spots left, just not a fan of rough kuro finishes.

I was thinking something that isn't extremely abrasive, maybe a wire brush attachment? Or any other ways to do it short of FeCl3?
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Perhaps a felt wheel would be a good option. I have heard it being used to clear the black stuff from rust pitting.
 
4wa1l said:
Does anyone know if there's a suitable dremel attachment that can remove small spots of kurouchi that lay inside indentations? I've sanded most of the kuro off a couple of knives but each have a few remaining deeper spots that I'd like to remove. Not looking for an even metal finish and honestly don't mind if there are still a few spots left, just not a fan of rough kuro finishes.

I was thinking something that isn't extremely abrasive, maybe a wire brush attachment? Or any other ways to do it short of FeCl3?
Click to expand...
There is also a brass wire brush wheel that works well. It's sually soft enough to not visibly scratch the steel.
 
4wa1l said:
Does anyone know if there's a suitable dremel attachment that can remove small spots of kurouchi that lay inside indentations? I've sanded most of the kuro off a couple of knives but each have a few remaining deeper spots that I'd like to remove. Not looking for an even metal finish and honestly don't mind if there are still a few spots left, just not a fan of rough kuro finishes.

I was thinking something that isn't extremely abrasive, maybe a wire brush attachment? Or any other ways to do it short of FeCl3?
Click to expand...
If it's scale in a forged surface, yes wirewheel is good. Other options are sandblasting or acidbath (hydrochloric)
 
Thanks for the help everyone! I'll get a wire brush and try a felt one too. I want to avoid any wet chemistries at this stage.

Will report back with results.
 
childermass said:
Maybe needless to say but use protective glasses when using the wire wheel in case some of the wires break off it’s better to not have them hit your eyes.
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Always good to say it. I've had one of the small cutting disks break on me in the past which could've been nasty.
 
Definitely worth doing if you put the time and effort heres my watanabe petty. Did not do any of the heavy lifting though. Only thing i did was polish and gave it a kasumi finish.
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Was initially done by nutmeg but it still had the wide bevel shoulders so i gave it to dave for thinning. Now it just goes through anything
 
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