Polishing progression

Discussion in 'Sharpening Station' started by metamorpheus, Jan 8, 2019.

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  1. Jan 8, 2019 #1

    metamorpheus

    metamorpheus

    metamorpheus

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    Currently polishing a Kurosaki KU AS and I'm nearly at a uniform 2k stone finish. I originally planned to move onto a Mizuhara 4k and finish with an ume 8k before moving to muddy 5-6k honyama and a Shobudani suita. Would the extra time on the synths be worth it compared with just using a Kouzaki aoto before the finishers?
     
  2. Jan 8, 2019 #2

    nutmeg

    nutmeg

    nutmeg

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    I don't know the particular stones you're using and can't see the real condition of your blade. You may not know the result you'r looking for.
    But.. even with a very time consuming polishing you can't erase all the scratches.
    So try to make the scratches look as beautiful as possible at every stage, without even thinking about the next stone.
    For example, with your #2000, if you get the 100% of the scratches 100% parallel to the axis of the blade the result will be perfect and perfect isn't always loaded with much character but perfect is generally not bad ;-)
    And after that, the next step is going to be safe.

    So, yes, extra time on the 2k/every stone!
     
  3. Jan 9, 2019 #3

    metamorpheus

    metamorpheus

    metamorpheus

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    Definitely spending extra time on 2k. Think I'm 5 hours in already and not quite done. This one had the grind marks from hell. Went Chosera 400, kohetsu 800, backwards to bamboo 150, cho 400, kohetsu 800, backwards to 80 grit sandpaper w/ mineral oil, 150 paper w oil, 400 w oil, 800 w oil, 1000 w water, 1500 w water, 2000 w water, backwards to Cho 400, Kohetsu 800, and these pics are maybe 80% through the Kohetsu 2k work.

    Right side:
    [​IMG]
    [​IMG]
    [​IMG]

    Left side:
    [​IMG]
    [​IMG]
     
  4. Jan 9, 2019 #4

    XooMG

    XooMG

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    I'm no expert, but if you don't mind my suggestion, stick with synthetics until the scratches on the core are to your liking, whether that's in terms of fineness or uniformity. Otherwise, a jump to coarser naturals may mask scratches a bit, but they'll haunt you when you move to finer stones.
     
    Stonetherapy likes this.
  5. Jan 9, 2019 #5

    zitangy

    zitangy

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    Mental strength and discipline at each grit.. till expectation met. Then move to next grit.

    pardon my asking.... why is the kurochi line so "sexy" ?

    Anyway ,i am a sandpaper man...

    Hve fun
     
  6. Jan 10, 2019 #6

    metamorpheus

    metamorpheus

    metamorpheus

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    I can see the truth in this with the limited experience I have. Masking of grind scratches while using lower grit synths has been a major issue on this project. I had a nice even finish on my 150 grit stone only to have those vertical devil scratches reappear. They extended all the way down through the hagane. I've removed maybe 90-95% of them from the knife and I'm paying a lot of attention to polishing the core. Decided I'll be using the Mizuhara 4k, Naniwa SS5k, and the Ume 8k. Should I skip the aoto then?
     
  7. Jan 10, 2019 #7

    metamorpheus

    metamorpheus

    metamorpheus

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    I've been working on this knife for a month. Not full time, but I've dedicated the majority of at least 5 days off and 1-2 hours a day. There's a point where one must accept good enough. I'll give it another 2-3 weeks, but really want to use this knife again. My backup is awful for onions.

    I like the dark rustic look of the knife minus the demonic scratches I've been working to remove. KU isn't for everyone I guess. I think a hazy mirror kasumi finish will look quite nice under the KU. The color gradient will go from darkest to lightest top to bottom until it patinas. Even then the lighter kasumi SS will look nice sandwiched inbetween.
     
  8. Jan 10, 2019 #8

    XooMG

    XooMG

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    Don't take my advice too seriously, but as long as the aoto or finer midgrit is clean and smooth, I think it can chase the 8k alright and will help re-fog the core and give the finer natural stones a bit more texture to bite into.
     
  9. Jan 10, 2019 #9

    zitangy

    zitangy

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    Thats quite alot of time spent.

    Rate of Steel removal....

    a) Grit
    b) pressure.. ON the stone, if you press hard perhaps you wld clock in abt 8 to 10 kg and wld be tired pretty fast. COmfortably an average person wld clock in abt 4 to 6kg per stroke .

    ON the videos most knife makers wld use 2 hands and with steel bar with wrapped sandpaper around it with the necessary width required and the knife is clamped. Because the pressure is more focused on a smaller area, fast steel removal.. I do wrap it a few times as i wld like to maintain the grind of knife.

    I like to do it standing up.... and like to lean into it... for added pressure.

    have fun and if you dont give it.. you will get there.... either slowly or fast... Perseverance

    Z
     

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